Business Mileage vs Commuting: The Rule That Catches People Out

It's the most common mileage mistake self-employed people make: claiming their daily commute as a business journey. HMRC's rules on business travel are clear, but the details trip people up, especially if you work from multiple sites or visit clients from home.

The basic rule

Your regular commute is not claimable. Driving from home to your normal place of work and back again is "ordinary commuting" in HMRC's language. It doesn't matter that you're self-employed. If you go to the same place every day, that journey is personal.

Business travel is claimable. This includes driving to client sites, supplier meetings, temporary work locations, or between two business premises. These are the miles that count towards your 45p/25p mileage allowance.

Where it gets interesting

The grey areas are where most people either miss legitimate claims or accidentally over-claim:

You work from home

If your home is your principal place of business (your office, workshop, or base), then driving from home to a client site is business travel. This is a huge one for freelancers, consultants, and sole traders who don't have separate premises. Every client visit, every supplier trip, every meeting: all claimable.

But "working from home" needs to be genuine. If you have a desk at home where you do admin but your real work happens at a rented unit, your home isn't your principal place of business; the unit is. HMRC looks at where you spend the majority of your working time and where the core activity of your business takes place. If you genuinely run your business from home (taking calls, doing quotes, managing invoices, storing tools), then home is your base and every journey from it to a client or supplier is business travel.

This matters enormously for the numbers. A mobile hairdresser working from home who visits 4 clients a day, each 6 miles away, racks up about 48 business miles per day. That's roughly 12,000 business miles per year, worth £5,500 in mileage allowance. If HMRC reclassified their home as "not the principal workplace" because they also rent a chair at a salon two days a week, those 48 daily miles could partially become commuting. The classification of your base matters.

You have a workshop and visit clients

Home to workshop = commute (not claimable). Workshop to client = business (claimable). Home to client = business (claimable, because it's not your regular commute). The key question HMRC asks: is this journey to your permanent workplace, or somewhere else?

You work on multiple sites

Tradespeople often work on different job sites. If no single site is your "permanent" workplace (you move between jobs), then travel to each site is typically business travel. But if you go to the same site for an extended period, HMRC may treat it as a permanent workplace, and your travel to it becomes a commute.

The 24-month temporary workplace rule

HMRC considers a workplace "temporary" if you expect to be there for less than 24 months. Once you know (or expect) you'll be at the same location for longer, travel to that site becomes ordinary commuting and stops being claimable. This catches contractors on long-term engagements.

The critical word is expect. The 24-month clock doesn't start when you arrive at a site; it's based on your reasonable expectation at the time. How it works in practice:

• You take a 6-month contract. Travel to that site is business. If the contract extends to 12 months, still business. If it extends again and you now expect to be there for over 24 months total, travel to that site stops being claimable from that point forward. You don't have to go back and reclaim the earlier months.
• You take an 18-month contract with a likely 12-month extension. If you know from the start that you'll probably be there for 30 months, it's not a temporary workplace from day one. Travel is not claimable.
• The 40% test. Even within 24 months, if you spend more than 40% of your working time at one location, HMRC can argue it's your permanent workplace. An IT contractor who goes to the same client office 3 days a week for 18 months is spending 60% of their time there; that's more likely to be treated as a permanent workplace even though it's under 24 months.

This rule is detailed in HMRC's Employment Income Manual (EIM32080). It's written for employees, but the same principles apply to the self-employed when determining whether travel is business or commuting.

Real examples by profession

Delivery driver

A self-employed delivery driver who collects parcels from a depot each morning has a tricky situation. If they go to the same depot every day, HMRC will likely treat that as their permanent workplace, so home to depot is a commute. But depot to each delivery address is business, and any miles driven between deliveries are business. If they work for multiple platforms and vary their starting point, the picture changes: no single depot is their permanent base, so more of the mileage is claimable.

Estate agent

An estate agent who works from a high street office has a clear commute (home to office). But property viewings, valuations, and vendor visits are all business travel. If they go straight from home to a 9am viewing before heading to the office, that first leg is business, because they're not going to their permanent workplace.

IT contractor

IT contractors on client-site engagements need to watch the 24-month rule carefully. A 12-month contract at a bank's offices is temporary, so travel is business. But if the contract rolls into a second year and you expect to be there beyond 24 months, your commute to that office stops being claimable. Many contractors miss this and continue claiming after the expectation changes.

Mobile hairdresser or beauty therapist

If you visit clients at their homes, every journey is business travel (assuming home is your base). This is one of the most straightforward scenarios. Home to client, client to client, client to home: all business. The key is that you don't have a separate salon that you go to regularly.

Care worker (self-employed)

A self-employed care worker visiting clients at their homes throughout the day can claim all travel between clients and from home to the first client and last client to home. But if they have a regular care home they attend every day, that's a commute. If they work across multiple homes with no fixed base, all travel is typically business.

Consultant

A management consultant working from a home office who visits different clients each week has one of the strongest positions for mileage claims. Home is the base, every client visit is business, and the variety of destinations makes the "temporary workplace" argument clear. A consultant doing 3 client visits per week at 30 miles each way generates about 7,800 business miles per year, worth £3,510 in mileage allowance.

The multiple workplace question

What if you have two workplaces? Say you have a home office where you do admin and a rented workshop where you build things. Which is your "permanent" workplace?

HMRC's view is that you can only have one permanent workplace (or, in some cases, none, if you're genuinely itinerant). The permanent workplace is typically where you spend the most time or where the core activity of your business takes place. Travel to your permanent workplace is commuting. Travel to any other workplace is business.

So if you spend 3 days at the workshop and 2 days at home, the workshop is likely your permanent workplace. Home to workshop is a commute. But workshop to client, home to client, and home to supplier are all business. Getting this classification right from the start saves arguments later.

Detours and mixed-purpose journeys

What happens when a business journey includes a personal stop? You're driving from your workshop to a client's house and you stop at Tesco on the way. Is the whole trip business, or does the Tesco stop contaminate it?

HMRC's general principle is that a journey must be "wholly and exclusively" for business to be claimable. But in practice, a minor detour doesn't usually disqualify the whole journey. The guidance distinguishes between:

• A detour on a business journey. You're driving to a client and swing by the petrol station. The main purpose is business. The entire mileage is claimable (though you wouldn't claim the small detour itself if it adds significant miles).
• A dual-purpose journey. You drive to a town to visit a client and also do personal shopping while you're there. If you wouldn't have made the journey without the business purpose, it's still claimable. If you would have gone anyway for the shopping, it's not.
• A personal journey with a business stop. You're driving to your parents' house and drop off an invoice to a client on the way. The journey is personal. You can't claim it just because you added a business errand.

The practical test: what was the main reason for the journey? If you'd have made the trip regardless of the business element, don't claim it. If the business purpose is the reason you got in the van, claim it.

Common HMRC challenge scenarios

If HMRC queries your mileage classification, these are the arguments they typically make and how to defend against them:

• "Your home isn't your principal place of business." Defence: show that you do substantive work from home (client calls, invoicing, stock management) and that you don't have a separate workplace you attend daily. Having a dedicated room, business insurance covering home use, or claiming use-of-home expenses all support your case.
• "This client site is your permanent workplace." Defence: show that your engagement was expected to last less than 24 months when it started, and that the expectation hasn't changed. Contract documents, correspondence, and invoicing patterns all help.
• "These journeys are personal, not business." Defence: a mileage log with the purpose of each journey noted at the time. "Client visit, J. Smith, boiler repair" is much stronger than a list of miles with no context.
• "You're claiming too many business miles for your type of work." Defence: detailed records showing every journey. If HMRC says "a typical plumber in your area drives 8,000 business miles" but you can prove 11,000 with a GPS log, the GPS log wins.

Journey examples at a glance

How to get it right

The safest approach is to classify every journey honestly and consistently:

1. Mark your regular commute as "commute". Don't try to claim it. HMRC knows where you work.
2. Claim everything that's genuinely business: client visits, supply runs, meetings. Many people under-claim because they're not sure what counts.
3. Add a purpose to business journeys, like "Client visit: Smith & Co" or "Supplier run: Toolstation". If HMRC asks, this is your evidence.
4. Keep records automatically. A GPS log with timestamps is much stronger than a guess. See the guide on what HMRC actually requires in a mileage log.
5. Review the 24-month rule regularly. If you've been going to the same site for a while, check whether your expectation has changed. Mark the date when it does, because that's when the classification flips.
6. Be consistent. If you classify home-to-workshop as commuting in April, don't suddenly start claiming it as business in October. HMRC will spot the inconsistency and question everything.

If you're ever unsure whether a journey is business or commuting, ask yourself: "Am I going to my regular workplace, or somewhere else for work?" If it's somewhere else, it's almost certainly business.

Classify every journey with one tap. Business, personal, or commute: KeptMiles keeps track so you don't have to guess.