How to Build a Holiday Let Business Plan That Actually Stacks Up

Most holiday let business plans get written backwards. Goals first, marketing second, the real numbers somewhere near the end. That order made sense a few years ago. It does not now, because the tax rules changed, the planning picture got more complicated, and a holiday let that worked well in 2023 might not clear the same bar today.

If you are sizing up a holiday let as your next investment, or your first one, the real risk is not a thin marketing plan. The danger is not poor arithmetic either. It is building accurate calculations on outdated assumptions, then finding that out once you have already exchanged. This guide puts the checks in the order they matter, so your plan is built on what is true now.

If you already have a property in mind, the quickest way through this is usually a conversation rather than a spreadsheet. Book a free call and we will talk through the numbers, the planning risk, and what is worth checking before you go further.

What a Holiday Let Business Plan Needs to Get Right First

A holiday let business plan has two jobs. One is proving the numbers work. The other is proving the property can legally operate the way you have planned. Most templates only do the first job, often using assumptions that have not been true since April 2025, and most investors spend far more time modelling income than they spend validating the assumptions sitting underneath it.

We see this gap most clearly across most of the conversions in our portfolio. The projects that work are the ones where the design and the investment case get solved together, not handed to separate advisers, which is the thinking behind what we call our Dual-Lens Approach.

Get the order right and the rest follows more easily. Tax treatment, planning status and registration come first, because they decide whether your numbers mean anything at all. Your target guest and your marketing plan come later, once you know the deal itself is sound.

Confirm the Tax Position Before You Build Any Numbers

For years, a furnished holiday let sat in its own tax category, with full mortgage interest relief, capital allowances on furniture and fittings, and access to certain capital gains reliefs that ordinary rental property did not get. That regime was abolished from 6 April 2025 for income tax and 1 April 2025 for corporation tax. Holiday lets are now taxed broadly in line with standard rental income. This is currently one of the biggest causes of inaccurate holiday let projections, because a plan built on the old regime can look profitable right up until an accountant recalculates it under the current rules.

This matters because mortgage interest relief is no longer fully deductible against your rental income the way it used to be. Build your return projections on the old rules and your real return after tax will be lower than your spreadsheet suggests, usually discovered only once an accountant looks at it properly, and pre-tax profitability and post-tax profitability are often very different investments.

Talk to an accountant who knows property before you finalise any numbers, and ask them specifically how your finance costs will be treated under the current rules, how ownership should be structured, and what the post-tax return actually looks like. Do not assume the old tax benefits still apply just because the property was previously run as a furnished holiday let.

Check the Planning and Registration Position

A holiday let differs most from a standard buy to let right here: planning and registration are two separate questions, and both need answering before you spend money on conversion or marketing. Most investors treat planning as an application to file. In reality, it is a viability test the property either passes or doesn’t, and that’s worth establishing before anything else moves forward.

Planning Risk and Material Change of Use

There is no single UK wide planning rule for holiday lets. Outside London, whether you need planning permission usually comes down to whether switching to short term letting counts as a material change of use, a judgement your local council makes, often after a complaint rather than before you start.

In Greater London, a residential property generally cannot be let short term for more than ninety nights in a calendar year without planning permission, where the property is the host’s main home. That is a rule specific to London, not a national one, so do not apply it anywhere else.

A new planning use class for short term lets has also been proposed, separate from standard residential use. It is not yet confirmed as fully in force everywhere, so check the current status with your local council, or with us, before assuming your conversion route is settled. Our holiday let planning use class guide covers the council by council variation in more depth.

Planning risk is also usually easier to identify before purchase than after. Strong investors verify planning assumptions before they exchange; weaker plans verify them afterwards, once the cost of being wrong has already landed.

The National Registration Scheme: What to Check First

England has been moving towards a mandatory national registration scheme for short term lets, requiring every property to carry a registration number before it can be advertised on platforms such as Airbnb or Booking.com.

Do not build your launch date around marketing the property until you have confirmed where the scheme stands. Compliance requirements like this are far easier to build into a launch plan than to retrofit once bookings have already started, and listing before you are compliant, once the scheme is live, risks the listing being removed.

Work Out Your Business Rates & Council Tax Position

Self catering holiday lets meeting certain occupancy conditions are assessed for business rates rather than council tax. The exact tests, covering how many days the property must be available to let and how many days it must actually be let, differ between England, Wales, Scotland and Northern Ireland, and some nations have adjusted theirs more recently than others.

Check the current thresholds with the Valuation Office Agency in England, or the equivalent body in your nation, and confirm which classification your council will actually apply. Small differences in ongoing costs like this can have a significant effect on your yield projections, so this decision belongs in your numbers rather than as an afterthought.

Many councils have also introduced premiums on council tax for second homes and holiday lets in their area. These are set locally, so check the specific council your property sits in rather than assuming a national rate.

Confirm Lease, Mortgage and Insurance Permissions

This step gets skipped more often than it should, usually because it feels like paperwork rather than strategy. It can sink a deal regardless of how good your numbers look. Many business plans fail because they assume finance will adapt to the strategy, when often it’s the strategy that needs to adapt to the finance.

If the property is leasehold, the lease may restrict or prohibit short term letting outright, so check this before you price the deal rather than after exchange. Standard buy to let mortgages are not usually designed for holiday let use, and lenders typically expect a dedicated holiday let mortgage with stricter criteria and a different rate. Your insurer also needs to know guests are short term, since a standard landlord policy may not cover it, and a gap in cover tends to surface at the worst possible moment.

Planning permission, registration, lease terms, mortgage terms, and insurance cover all link together. Breaking any one of them quietly weakens a plan that otherwise looks sound.

Build the Financial Model and Decide Who You Are Letting To

Once tax, planning, registration and your rates position are all confirmed, you are modelling real numbers instead of assumptions. A solid business plan example for a holiday let includes purchase and conversion costs, the mortgage product and rate you have actually secured, realistic occupancy rather than a best case guess, and the tax and rates position you have now checked. Run it conservatively first. If the deal only works on best case occupancy, it is not a deal yet. It is a hope. Ask what happens if occupancy comes in lower, tax treatment shifts, planning conditions change, or finance costs rise: good investments survive those conservative assumptions, while great assumptions on their own don’t create a good one.

Your holiday let business model takes real shape here too. Are you targeting couples on a quiet break, families who need space and flexibility, or a higher spec stay built around a specific local draw? Your target guest should shape the design before it shapes the marketing, since it influences pricing, the standard of finish, and how hands on the management needs to be. If the interior choices are still undecided, our Airbnb interior design guide looks at what actually influences bookings, not just what looks good in photos.

Decide early whether you will manage cleaning, guest communication and maintenance yourself, use property management software, or bring in a management company. Doing it yourself protects margin but costs time, while a company buys back your time at the cost of margin. Choose based on how hands on you actually want this to be, not on which option sounds more professional.

Common Mistakes That Sink a Holiday Let Plan

Four assumptions break more holiday let business plans than anything else, and they map directly onto the checks above. The most common is modelling returns on tax assumptions that predate the 2025 change, then discovering the real return after tax only once an accountant reviews the figures, sometimes after the purchase has gone through. Close behind it is leaving planning unchecked: pricing a leasehold flat without confirming whether the lease allows short term letting, or assuming a conversion route is settled when it hasn’t actually been confirmed. Treating registration as something to deal with later is the third, since later can mean after you are already taking bookings. The fourth is assuming the business rates test is the same wherever the property sits. It is not, and getting it wrong quietly erodes a margin you thought was safe.

What to Do Next

If you have worked through the checks above, the next useful step is testing your actual numbers rather than estimating them. Our Deal Analyser lets you run your costs, VAT and projected returns against a real property, so you are working from a model rather than a guess.

Numbers are only half the picture, though. A free discovery call is where we look at your actual project: what you are trying to achieve, how a property like yours tends to play out once planning and tax are factored in, and where HMO Architects can genuinely help.

Looking at a specific property? Stress-test the assumptions before building the spreadsheet. Planning a conversion? Verify the planning and tax position before committing capital. Building a holiday let portfolio? Judge each new property against the same checks rather than assuming what worked on the last one still applies.

For more of this kind of detail as the rules keep shifting, our newsletter covers changes like these as they happen, rather than after the fact.

FAQs

Do I Need Planning Permission for a Holiday Let?

Whether you need planning permission turns on your council’s view of whether switching to short term letting counts as a material change of use. There is no single national rule outside London’s ninety night cap, so check with your local planning authority before assuming either way.

What Happened to the Tax Relief on Furnished Holiday Lets?

The furnished holiday let tax regime was abolished from 6 April 2025 for income tax and 1 April 2025 for corporation tax. Holiday lets are now taxed broadly the same as standard rental property, including restrictions on finance cost relief that used to be fully deductible.

Do I Need to Register My Holiday Let in England?

A national registration scheme has been developed for short term lets in England, but its exact live status should be checked on GOV.UK rather than assumed, since the timeline has shifted more than once. Do not market or list a property assuming registration will not be required.