Self-Employed Mileage - Nailing Down What I Can Claim

So, you're self-employed and using your own car or van for work, right? I remember when I first started out, the thought of tracking every single penny spent on my car for business felt like a mountain to climb. Then I stumbled upon the mileage allowance, and honestly, it was a bit of a game-changer. Instead of hoarding fuel receipts like a dragon with gold, I found a much simpler way to get some tax relief.

I used to really stress about missing a receipt or getting a calculation wrong. But this system, once I got to grips with it, made things so much smoother. I want to walk you through how it works for me, how I figure out the numbers, and what kind of trips actually make the cut, so hopefully, you can feel more confident about claiming what you’re due.

Breaking Down "Self-Employed Mileage Allowance" – My Take

Whenever I jump in my car for a work thing – whether it's meeting a client or picking up supplies – I know those miles are more than just travel; they're a potential way to lighten my tax load. Getting clear on how this whole thing operates has been crucial for me. It not only helps keep my business expenses looking healthy but also means I'm not overpaying Uncle Sam.

The Nitty-Gritty: Mileage Allowance as I See It

At its heart, the self-employed mileage allowance is basically a flat rate that HMRC says I can use. It means I can calculate my business vehicle expenses without having to itemize every last thing. So, instead of saving every fuel receipt, repair bill, and insurance document (though I still keep major ones for other reasons!), I just focus on keeping a good record of my business miles. Then, I use the rates HMRC provides.

For my car (and it’s the same deal for vans), they’ve set it at 45p a mile for the first 10,000 business miles I do in a tax year. If my business travel goes beyond that, then any extra miles are at 25p. If I were zipping around on a motorbike for work, that’d be 24p a mile. The absolute key for me is noting down every business journey – dates, where I went, why I went, and how many miles it was. That way, my records are always tidy and ready if HMRC ever has a question.

What I really like is that this allowance isn't just for petrol. It’s meant to cover the general wear and tear on my car, a bit for maintenance, and that slow drop in value cars always have. It just makes that part of my admin feel much more straightforward.

Why Bothering with Mileage Claims Matters So Much to Me

Let's be honest, claiming my mileage allowance directly shaves a bit off my taxable profit. And what that means in plain English is I pay less income tax. That's cash that stays with me, which I’d much rather have than sending it off to HMRC if I don’t have to!

Instead of feeling like I'm constantly chasing my tail with a pile of tiny receipts, I just log my trips and use these set rates. It’s really simplified my tax records and makes that annual self-assessment feel a bit less like a monster. Since I do use my car quite a bit for work, those savings genuinely make a difference over the year.

And, you know, doing it correctly means I'm playing by the book. That gives me a certain peace of mind, knowing I’m ready if HMRC ever wants to look at my numbers. Getting into good habits here has saved me from potential headaches, believe me.

Who Can Actually Claim This? My Situation

I can claim mileage allowance because I’m a sole trader. If I were in a partnership, that would work too. The main thing for me was that I hadn’t already tried to claim capital allowances or the actual, itemised running costs for the same car. Also, this simpler mileage method is generally for folks whose business turnover is below the VAT registration threshold when they first start using it for a particular vehicle.

Now, if I was driving a "company car" – like one owned by a limited company, even if it was my own limited company – or if I was borrowing someone else's car for work, then this mileage allowance wouldn't be for me. One thing I always have to drum into my own head is that I can only claim for actual business journeys. My trip from my house to my main workshop every day? That doesn't count. But driving out to see a new client, or going to a trade show, or picking up specific materials for a job? Absolutely, those are in.

To make sure I’m still good to go, I always give my records a once-over to check they’d pass muster with HMRC and that I haven’t let any personal journey miles sneak in. Sticking to the guidelines is my best bet if my accounts ever get a closer look.

The Current HMRC Mileage Rates – The Numbers I Use

These rates from HMRC are what my whole claim is built on. Knowing them, and how often they might (or might not!) change, really affects how much I can knock off my tax.

Getting My Head Around the Approved Rates

So, HMRC gives us these specific rates for when we use our own cars for business. Like I said, for my car, it's 45p a mile for the first 10,000 miles in any given tax year. After I cross that 10,000-mile line, any business miles on top of that are at 25p.

If I had a motorbike for business, I’d be using 24p for every business mile. And for anyone using a bicycle for work trips (good on you!), that’s 20p a mile. These rates are supposed to be an all-in-one figure, covering petrol, wear and tear, and those other general running costs.

It’s super important for me to remember this is all because I’m using my own vehicle. It’s not for company cars. And, if a client or an employer (if I was doing employed work on the side) paid me more per mile than the HMRC rate, I’d have to be upfront about that extra bit and pay tax on it.

Just so it’s clear, here are those main rates again:

- My Car (or Van): 45p for the first 10,000 miles, then 25p after that.

- Motorbike (if I had one): 24p for all business miles.

- Bicycle (for the super keen!): 20p for all business miles.

How Often Do These Rates Actually Get Tweaked?

HMRC does look at these mileage rates, but they don’t just change them willy-nilly every year. If they do make changes, it’s usually down to big shifts in things like fuel prices, average car running costs, or sometimes just tax policy changes.

To be honest, the rates for cars and vans have been the same 45p/25p since way back in 2011! The motorbike and bicycle rates have also been pretty steady for ages. This consistency is actually quite helpful for planning, but I still make it a little ritual to just quickly check the HMRC website before a new tax year kicks off, just in case they’ve decided to surprise us.

If a change is coming, HMRC usually lets everyone know before the new tax year starts on April 6th. I’ve just got into the habit of doing that quick check before I finalise my claims – just so I know I’m using the latest figures and not tripping myself up.

How I Work Out My Mileage Allowance

Figuring out my mileage allowance is mostly about being accurate and keeping my records in good shape. The biggest thing for me is carefully tracking my actual business journeys and making sure I separate them cleanly from any personal driving I do.

My Step-by-Step Way of Calculating Miles

First off, I keep a log. I used to use a little notebook, but these days I often use an app on my phone because it’s just easier to have it with me. For every single business trip, I make sure I note:

- The date I made the journey.

- Where I started from and where I was headed.

- The total miles I drove for that specific trip (I usually use Google Maps to check if I'm unsure).

- And just a quick note on why I made the trip – like "Client meeting with Sarah B," or "Picking up supplies from Trade Paints."

- I really try to jot these down pretty much straight after a trip, or at least the same day, because trying to remember details from weeks ago is a recipe for mistakes or missed miles.

Then, usually at the end of each month or definitely at year-end, I add up all those business miles. Once I have my total, I apply the HMRC mileage rate. So, for the 2024/25 tax year, it’s that 45p per mile for the first 10,000 miles, and 25p per mile for anything over that.

Let me try and paint a picture:

Say I drove 9,000 business miles in the tax year. My claim would be: 9,000 miles x £0.45/mile = £4,050. Pretty simple.

But if I drove, say, 12,000 business miles, it’d break down like this:

- First 10,000 miles x £0.45/mile = £4,500

- The next 2,000 miles x £0.25/mile = £500

So, my total claim would be £4,500 + £500 = £5,000.

I always, always keep my logs and any printouts of my calculations somewhere safe. If HMRC ever asks, I want to be able to show them exactly how I got to my figures. I know that if my logs are a mess or look a bit dodgy, they could easily question my claim.

The Really Important Bit: Business Miles vs. Personal Miles

This is where I have to be super disciplined. I can only claim for journeys that are 100% for business. If I'm out on a business trip and think, "Oh, I'll just nip to the supermarket on the way home," I can only count the miles for the business part of that journey. HMRC is pretty clear: my regular drive from my house to my workshop (my permanent place of work) doesn't count. That’s just commuting.

So, if I go to see a client, and then on the way back I detour to do my weekly shop, I only log the miles to the client's place and what would have been the direct route home from there. The extra loop for the groceries is on my own dime. If a journey is a genuine mix of personal and business, I have to make a fair and honest stab at figuring out the business bit.

I always try to take a breath and double-check a journey in my head before I log it. Getting personal and business miles tangled up is a surefire way to cause myself problems, or just end up claiming the wrong amount.

Getting My Mileage Allowance onto My Tax Return

Putting my mileage allowance claim in correctly on my tax return really does make a tangible difference to how much tax I cough up each year. As a self-employed bod, it’s so important for me to get this right. It avoids silly mistakes that could cost me money or, even worse, get me on HMRC’s naughty list.

How I Tackle the Self Assessment Form

When it's that time of year for my Self Assessment tax return, I make sure my mileage allowance is included as part of my business expenses. Once I’ve got all my eligible business miles logged and totalled up for the tax year, I use those HMRC approved rates: 45p a mile for the first 10,000 miles, and then 25p a mile for any car or van miles on top of that. (If I were on a motorbike, it’d be that flat 24p per mile).

I pop the total amount I'm claiming into the section for "Vehicle, travel and subsistence costs." This is particularly if I'm using what HMRC calls 'simplified expenses' – which the mileage allowance falls under. One thing I’m super careful about is not mixing methods for the same vehicle in the same year. If I tried to claim some actual individual fuel receipts and the mileage allowance for my car, HMRC would not be happy. So, I pick one method for the year for that vehicle and stick to it. HMRC can ask to see my mileage log, so keeping that detailed record throughout the year – with dates, miles, and the business reason for each trip – is non-negotiable for me.

Common Slip-ups I've Learned to Sidestep

It’s surprisingly easy to make a boo-boo with mileage claims, but just being aware of the common traps has saved me a fair bit of grief over the years.

- Only true business journeys: I can't say this enough – those trips between my home and my regular, fixed workplace? They don’t count.

- Keep personal trips out: Any journey that's just for me, or a personal detour on a business run, has to be left out. Overclaiming is a fast track to trouble.

- One method per vehicle, per year: Generally, once I’ve picked the simplified mileage method for my car, I have to stick with it for as long as I use that car for business. Chopping and changing to actual costs for the same car isn't usually on the cards. So, I make a decision for that vehicle each year.

- Check my maths! Sounds daft, but a simple adding-up error is a really common reason for HMRC to send a query. I always give my numbers a second look.

- Keep those logs fresh: This means I can actually prove my claim if asked, and it also stops me from forgetting trips I made months ago.

My Approach to Keeping Mileage Records

To make sure I claim the right amount on my self-assessment, I know I’ve got to keep solid, accurate mileage records. I could use paper or go digital – HMRC doesn't mind which – but they do have specific things they want to see. Personally, I’ve found digital tools can be a real time-saver and cut down on the faff.

What I Make Sure My Records Show for HMRC

If HMRC ever decided to look into my mileage claim, they'd want to see pretty detailed records. So, as a bare minimum, for every single business journey I make, I record:

- The date I made the trip.

- Why I was travelling (e.g., "Client X meeting," "Supplier Y visit," "Dropping off business post").

- Where I started from and where I ended up (postcodes are great if I can).

- The total miles I travelled for that specific trip.

I always keep in mind that it's only business journeys I can claim for – my personal drives and any regular commuting are definitely out. My log needs to show each journey as a separate entry; just a weekly or monthly summary of miles isn't detailed enough for them.

Even though I'm using the flat-rate mileage allowance (which means I don't need to keep every little fuel receipt for this specific claim), I absolutely, positively still need that detailed mileage log. I make sure I hang onto these records for at least 5 years after the 31st January submission deadline for that tax year. You never know when they might want to look back.

Digital Tools That Make My Life Easier

I’ve pretty much ditched paper logs now and mostly use mobile apps or a good old digital spreadsheet. I’ve found apps like MileIQ or Tripcatcher (there are loads out there) can really help make the whole thing smoother. Even a well-set-up spreadsheet on my phone or computer does the job.

The brilliant thing about some of these apps is that they can track my mileage automatically using my phone's GPS. That means I'm much less likely to forget to log a trip. Most of them then let me easily swipe or tap to say whether a trip was 'business' or 'personal' later on, which makes sorting out my claims at the end of the month or year a doddle.

Some of these tools also let me get a summary of my trips out into an Excel file or a PDF. I can then just keep this with my tax stuff or even attach it if I'm filing my return with software. The main thing for me, no matter what system I use, is that my records are spot-on, complete, and have all the info HMRC would want to see if they asked.

When I'd Think About Using Actual Costs Instead

Sometimes, after I’ve had a look at the numbers, it just clicks that claiming my actual vehicle expenses makes more financial sense than just sticking with the fixed mileage allowance. If I go down that road, it means I can deduct a fair proportion of every single allowable penny I've genuinely forked out to run my car or van for business.

Weighing Up Mileage vs. Actual Expenses: My Internal Debate

With the mileage method, I’m using that straightforward set rate per mile. It’s simple, yes, but it might not always cover what I’m really spending, especially if my car is a bit of a gas-guzzler or needs a lot of TLC. If I claim actual costs, though, I can claim a business percentage of pretty much every real vehicle expense. That includes stuff like:

- All my fuel.

- Servicing and MOT costs.

- My insurance premiums.

- Any repair and maintenance bills.

- Even things like breakdown cover or the interest on a car loan if I took one out to buy the vehicle for business.

- And depreciation – though this is usually handled through something called capital allowances, which is a bit more involved.

Here’s a quick way I look at it:

- Mileage Allowance: One rate covers most things. Simpler admin.

- Actual Costs: I claim a business-use slice of individual costs (fuel, insurance, repairs, etc.). Needs much more detailed record-keeping, but could mean a bigger claim if my costs are high.

If I use my vehicle like crazy for business, or if my running costs shoot up one year (maybe a big, unexpected repair bill), then taking the time to calculate actual expenses can sometimes mean I get a larger tax deduction. The downside is, I have to be like a hawk with my receipts, keeping every single one, and then I need to work out the exact business percentage for each and every cost. That definitely takes a lot more effort and time.

The Upsides and Downsides I Consider

For me, the biggest plus of thinking about actual costs is that I might get to deduct more if my vehicle is particularly expensive to keep on the road, or if I’ve had a year with some whopper bills. For example, if I’d just bought a brand-new van specifically for my work, or if my trusty car suddenly needed a new engine, the actual expense method could really help soften the blow on my tax bill.

But – and it's a significant "but" for me – it does mean a whole lot more paperwork and admin. I’d need to religiously keep every receipt, every petrol slip, every insurance certificate, and keep them all neatly filed, just in case HMRC fancies a look. Also, if I were to switch from using the mileage allowance method to actual costs for a vehicle, I need to be really careful about how things like capital allowances are handled. I generally can't claim certain allowances like the Annual Investment Allowance if I've previously used mileage rates for that same vehicle. That’s a big one I’d have to get proper advice on.

So for me, it's always a bit of a juggling act. Do I want the super-simple mileage allowance, or do I think I could maximise my deduction by going the actual costs route? If my car is fairly economical and I don’t rack up a massive number of business miles, the mileage allowance is probably the easiest and good enough. But if my business mileage is huge, or if my vehicle costs suddenly go through the roof, then it’s definitely worth my while to sit down with a calculator and see if switching to actual expenses would save me more tax in the long run.

Mileage Allowance for Different Wheels I Might Use

The mileage allowance rates I can tap into actually change depending on what kind of vehicle I’m using for my business runs. It’s not just a flat rate for everything, so my car has different rules compared to, say, a motorbike or even a pushbike.

Cars vs. Vans – What I Know

When I use my car (or if I had a van) for business trips, HMRC gives us what they call Approved Mileage Allowance Payments (AMAP) rates. For this current tax year (2024/25 as I’m writing this), it’s that 45p per mile for the first 10,000 business miles I clock up. After that, it drops to 25p per mile for any business miles beyond the 10k mark. This rate is supposed to cover all the usual suspects: fuel, a bit for wear and tear, insurance, general running costs.

A neat little extra I learned about is that if I give a colleague or a business contact a lift in my car for a work reason, I can actually claim an extra 5p per mile for each passenger. The main mileage rates themselves are the same whether I'm in my own car or my own van. HMRC doesn’t split hairs between cars and vans for us self-employed folk claiming mileage, which definitely makes life a bit simpler.

I always have to remind myself that these rates are off the table if I was using a leased car where my business pays the lease costs directly, or if I’d already decided to claim my actual running costs instead of this simpler mileage method. I can’t have my cake and eat it by claiming both mileage allowance and itemised actual running costs for the same vehicle in the same tax period. I’ve got to pick one lane and stick to it for each vehicle I use for work.

Motorbikes, Bicycles, and Other Ways to Get Around

Now, if I decided to use my motorbike for business, HMRC has a different rate for that: it’s a straight 24p per mile, for all business miles. There’s no tiered system with that 10,000-mile threshold like there is for cars and vans. And if I was really keen and used my bicycle for a business journey, HMRC lets me claim 20p per mile. For both motorbikes and bicycles, these rates are, again, designed to be all-inclusive. So, I couldn't claim separately for things like a new helmet or bike chain on top of that mileage rate.

What if I used something a bit out of the ordinary for a business trip, like an electric scooter or something? In those more unusual cases, HMRC doesn’t currently have a specific set mileage rate. So, if that was me, I’d have to go down the path of claiming my actual costs. That would mean keeping receipts for things like charging it, any maintenance, and then working out what proportion of its use was for business. For any vehicle I use, the most important thing is to log my mileage really clearly. And if a journey was a mix of personal and business use, I know I’d need to keep even more detailed notes to back up my claim.

Just to see them side-by-side:

- Car/Van: 45p (first 10k miles), then 25p. (Plus 5p per business passenger if I have one).

- Motorbike: A flat 24p for all miles.

- Bicycle: A flat 20p for all miles.

Tricky Mileage Situations I’ve Thought About

Sometimes, trying to claim my business mileage isn't completely cut and dried. Things can get a bit more complicated, especially if I was trying to run more than one business, or if, like me, I mostly work from my house. Knowing exactly which journeys are fair game and how I need to keep my records becomes even more critical in these kinds of scenarios.

If I Was Juggling Multiple Business Hats

If I were running, say, two different self-employed businesses at the same time (maybe I do some freelance writing and I sell crafts online), I'd have to be super careful to track my mileage separately for each one. This would mean my records would need to be really detailed, clearly noting which business each specific car trip was for. If I started mixing up journeys or wasn't clear about which business a trip belonged to, it could all get very messy if HMRC ever wanted to see the details.

Let's imagine I had to visit Client A for my writing business, and then Supplier B for my craft business, and I managed to do both on the same car journey. In that case, I'd need to carefully split the mileage based on each business's share of that overall trip. For instance, if one stop was much further away than the other, I'd have to apportion the miles fairly. If, by some chance, the entire trip was genuinely essential for both businesses equally (which would probably be quite rare), I’d still need to find a logical and reasonable way to divide the mileage – maybe based on how much time I spent on each business activity during that trip, or the direct distance to each location.

Here’s how my brain would try to tackle it:

- Visiting one client for Business X, then another for Business Y on the same day out: I’d log the miles to Client X as being for Business X. Then, the miles from Client X to Supplier Y would be for Business Y. And the return journey would need to be split or attributed fairly too.

- A single journey that really does serve both businesses at the same time: This would be the trickiest, but I’d aim to split the mileage based on something sensible, like the proportion of business I expected to do, or the time I dedicated to each venture during that specific trip.

The absolute golden rule for me here would be amazingly clear and accurate records. My log would need all the usuals – dates, exact reasons for trips (making sure to say which business it was for), start and end points, and the distance travelled, all clearly linked to the correct business.

When My Home is My Office

Since I do most of my work from my home, I’m always pretty cautious about what mileage I claim. Only the miles I drive for genuine, specific business reasons can be counted. My regular "commute" – even if that was just from my house to a local coffee shop I sometimes work from as a change of scene – wouldn't qualify as business mileage. HMRC sees that kind of regular trip to a fixed spot as ordinary commuting, and that’s not something I can claim mileage for.

However, because my home truly is my main and principal place of business (and for me, it is), then when I travel from my home to go and see clients, or to visit suppliers, or to attend business-related training courses, or even to run specific business errands like going to the post office to send business packages, I can claim those miles. To make sure I can back this up if ever asked, I always ensure I’ve got things that show my home is my operational base – like my business address being my home address on invoices, records of my work patterns, and just the general nature of how my business is set up.

It’s also worth me remembering that occasional travel to a temporary workplace (like going to a client's office for a few days to work on a specific project) can usually be claimed as business mileage. But, if I started making regular, almost daily journeys to that same "temporary" site for a long period, HMRC might start to see that site as a permanent workplace for me. If that happened, those journeys could then flip over to being classed as non-claimable commuting. It can be a bit of a fuzzy line sometimes, so I always try to be super clear in my records and use my common sense.

Common Mistakes with Mileage I Try Hard to Dodge

Over the years, I’ve definitely become aware of a few common tripwires that people (and yes, probably me in my early days!) can fall over when it comes to mileage allowance. Knowing what these are helps me keep on the straight and narrow.

- Sloppy records: This is probably the biggest one. If I didn’t keep a proper log with dates, where I went, why I went, and the mileage, I’d be asking for trouble if HMRC ever wanted to check.

- Blurring the lines between personal and business miles: It’s such an easy mistake to make. I always have to consciously keep them separate. When I’m busy, it might be tempting to just lump things together, but I know deep down that only the purely work-related parts of any trip can be claimed.

- Trying to claim for things the mileage rate already covers (or doesn't): For instance, those mileage rates are designed to include fuel and general running costs. So, I can't claim the mileage rate and then also try to claim for fuel separately for the same journey. Also, things like parking fines (oops!), road tolls, or the actual purchase price of my car aren’t covered by the standard mileage rates. (Though, things like tolls and business parking can sometimes be claimed as separate, distinct business expenses if I keep good records of them – they just aren't part of the mileage rate itself).

- Forgetting to check if the rates have changed: Okay, they haven’t shifted in ages, but if I just assumed and used an old rate by mistake one year, all my calculations would be out. I always do a quick mental check or a quick search online at the start of a tax year.

- Leaving my log until the last minute: If I try to reconstruct all my journeys at the end of the tax year, it’s a nightmare! I’d be bound to forget details, or even miss out on claiming for trips I genuinely made for work. Little and often is my motto here.

- Not knowing the rules are different for different vehicles: The way I claim for my car is different from how I’d claim if I used a motorbike or a bicycle for business. I need to make sure I’m applying the right logic and the correct rates for whatever I’m using.

- Sticking blindly to one method without thinking: Lastly, I sometimes hear from other self-employed folk who just use the mileage allowance year in, year out, without ever stopping to think if claiming their actual costs might actually be better for them in a particular year. Especially if they’ve had a year with really high vehicle expenses, it’s always worth a quick comparison.

Handy Places I Look To for Mileage Info

To keep my mileage records on point and make sure I’m not missing any new rules, I have a few go-to places for information. Here are some that I’ve found genuinely useful:

The HMRC Website Itself

This has to be my number one spot for anything official. The HMRC website (gov.uk) has all the proper guidance on mileage allowance, what you can claim tax relief on, the current approved rates, and they even have some examples and sometimes calculators.

- What I usually search for on their site is something like: "HMRC simplified expenses for self-employed" or "HMRC travel costs."

Mileage Tracker Apps – My Little Helpers

I’ve found that using an app on my phone makes tracking my business miles when I’m out and about so much less of a chore. There are absolutely loads of them available, but a couple that I’ve either used or heard good things about are:

- MileIQ: This one’s pretty clever at tracking your journeys automatically, which I find really handy. (You can get it for iOS or Android).

- TripLog: I’ve heard this one has good features for making custom reports, which could be useful. (Also on iOS/Android).

- Of course, many people just use a good spreadsheet app on their phone or computer, and if that works for you, that’s perfectly fine too! The best tool is the one you actually use.

Questions I Used to Ask Myself (And Still Sometimes Do!)

When I first started trying to claim mileage as a self-employed person, my head was spinning with questions. I’ve since learned that I just need to follow HMRC’s rules as carefully as I can – about the rates, how I keep my records, and how I put it all on my tax return. It’s really so important for me to be clear on which of my journeys actually count, how I should work out the relief I’m due, and where all these details actually go when I fill in my tax forms. Here are some of the big questions I had to figure out:

So, how do I actually work out my allowable mileage expenses for my self-employment?

For me, it all comes down to using those approved mileage rates from HMRC. For my car, that means I use 45p per mile for the first 10,000 business miles I drive in a tax year. If I go over that, then any extra business miles are at 25p per mile. If I happened to use a motorbike for work, that would be a simpler flat rate of 24p for every business mile. All I do is multiply the total business miles I’ve driven by the correct rate for that type of vehicle and that mileage band.

Can I claim for my commute now that I’m self-employed?

Ah, the age-old question! And the answer is still generally no. My normal journey from my home to a regular or permanent place where I do my business (like my workshop or a permanent office space if I had one) doesn’t count as allowable business mileage. HMRC just sees that as ordinary commuting, like anyone else going to work. However, when I travel from my business base (which for me is home) to see different clients at their locations, or if I have to go to temporary work sites for specific projects, then those journeys usually do qualify.

What’s the actual process I follow to claim mileage allowance relief on my Self Assessment?

When it’s time for me to tackle my Self Assessment tax return, I make sure I list my total business mileage claim. If I’m using the mileage allowance method (which HMRC often calls 'simplified expenses'), I just apply the flat rates to my total business miles. I could choose to claim my actual vehicle expenses instead (things like a proportion of my fuel bills, insurance, repairs, etc.), but with the mileage allowance, it’s much more straightforward – it’s just my business miles multiplied by the appropriate rate.

Where on earth do I put my mileage claim on my Self Assessment tax return?

This confused me at first! I enter my mileage expenses in the self-employment section of my Self Assessment form (that’s usually the SA103 form or its online equivalent). There’s a specific box or area for allowable business expenses, and it’s often labelled something like "Car, van and travel expenses" or similar. That’s where I put my total mileage claim figure for the year.

How much tax do I actually save with this mileage relief when I'm self-employed?

The actual amount of tax relief I get back in my pocket (or rather, don't have to pay out) depends on two main things: my income tax rate for that year, and the total amount of my business mileage claim. So, for example, if my total mileage claim for the year worked out to be £2,000, and I’m a basic rate taxpayer (which is currently 20% in most of the UK), then I effectively save 20% of that £2,000. That means my tax bill would be reduced by £400. If I was in a higher tax band, the saving would naturally be bigger.

What kind of proof do I really need to keep for my mileage claims when I do my self-employment tax?

This is super important: I absolutely have to keep detailed records. The main thing HMRC would want to see is a mileage log. This log needs to show, for each business journey, the date I made it, where I started from and where I ended up, the specific business reason for the journey, and the number of miles I drove for that trip. HMRC can ask to see these records at any time (and they can ask to see records from previous years too), so I make sure I keep them all safe and sound for at least five years after the January 31st tax return deadline for that particular tax year. Better safe than sorry, that’s my motto!