You are a couple of months from the end of your fixed rate, the new pay rate on offer looks a lot higher than the one you have been enjoying, and you have two questions. Can you still pull some equity out to fund the next deposit? And will the rent actually pass the lender's sums at these rates? Those are the right questions to ask, and in 2026 the answers are tighter than they were a few years ago.
The two questions that actually decide it
Everything about a buy-to-let remortgage comes down to loan-to-value (how much you want to borrow against the value) and the interest coverage ratio, or ICR (whether the rent covers the interest by enough margin). Get both to work and the rest is paperwork. Miss on either and no amount of shopping around fixes it.
Releasing equity: how much can you actually pull out
Most buy-to-let lenders cap you at 75% LTV, some at 80% for stronger cases. The equity you can release is the gap between your current balance and that ceiling, minus fees.
Worked example: a £250,000 flat
Say your rental flat is now valued at £250,000 and you owe £140,000. That is 56% LTV, so on paper there is room.
- Maximum loan at 75% LTV: £187,500
- Current balance: £140,000
- Gross equity released before fees: £47,500
That £47,500 is real, but it only lands in your account if the rent supports a £187,500 loan under the stress test. This is where a lot of applications stall.
The stress test in 2026: why the rent has to work harder
Lenders do not test your rent against the actual pay rate. They test it against a higher stressed rate, and they require the rent to clear that stressed interest by a margin (the ICR). Typical numbers at the time of writing (July 2026):
- 125% ICR for basic-rate taxpayers and limited companies
- 145% ICR for higher-rate taxpayers
- A stress rate often around 5.5%, or the product rate plus a margin, varying by lender
The higher band for higher-rate individuals is a knock-on effect of Section 24, which restricts mortgage-interest relief for individuals to a 20% basic-rate tax credit (gov.uk guidance). Companies still deduct interest in full, which is one reason lender ICRs are kinder to corporate borrowers.
Here is the same £187,500 loan under three common scenarios.
| Scenario | Stress rate | ICR | Annual interest | Rent needed (monthly) |
|---|---|---|---|---|
| Basic-rate, 2-year fix | 5.5% | 125% | £10,313 | £1,074 |
| Higher-rate, 2-year fix | 5.5% | 145% | £10,313 | £1,246 |
| Higher-rate, 5-year fix | 5.29% | 145% | £9,919 | £1,199 |
Now put a real rent against it. Suppose the flat lets for £1,150 a month, or £13,800 a year. A basic-rate borrower clears the £1,074 hurdle comfortably and gets the full £47,500. A higher-rate borrower on a two-year fix needs £1,246 and falls short, so the lender would cut the loan until the sums balance, releasing less equity than hoped.
The gap between passing and failing is often a few hundred pounds of monthly rent, so it pays to model your own figures before you apply rather than after a valuation. You can run the numbers for your own property with our mortgage stress test calculator and see how much a change in rate or rent moves your maximum loan.
The five-year fix quirk worth knowing
Many lenders apply a gentler stress test to five-year fixes, sometimes testing at the actual pay rate rather than pay rate plus a margin. In the table above, the five-year higher-rate scenario needs £1,199 against £1,246 for the two-year deal. If you are borderline on affordability, a longer fix can be the difference between the loan you want and a trimmed one, even before you factor in the rate certainty. The trade-off is a longer commitment and usually longer early repayment charges, so weigh it against your plans for the property.
Timing the move off your fixed deal
Timing is the part landlords most often get wrong, in both directions: leaving it too late and slipping onto the lender's standard variable rate, or jumping too early and paying a penalty.
Watch the early repayment charge
During a fixed term you will usually face an early repayment charge (ERC), often stepped from around 5% in year one down to 1% in the final year. On a £140,000 balance, even a 2% ERC is £2,800, which can wipe out the benefit of moving a few months early. As a rule, do not break a fix to remortgage unless the saving clearly beats the ERC plus the new arrangement fees.
Start early, but not too early
Mortgage offers are typically valid for three to six months. That means you can line up a new deal well before your current one ends and have it complete the day the old rate expires, with no gap on the standard variable rate. A sensible window is to start the process about four to five months out:
- Five months before: get a rough valuation and check your likely LTV band.
- Four months before: run the stress test at current rates and decide equity release vs a straight rate switch.
- Three months before: apply, so the offer is in hand before your ERC-free date.
- Completion: time it for the day after your fix ends to avoid both the ERC and the SVR.
Bank of England base rate and specific product rates move often, so treat any rate you see as accurate only on the day. Check the current Bank Rate and live product rates before you commit.
Product transfer vs full remortgage
If you do not need to release equity, a product transfer with your existing lender is worth pricing up. It usually skips the affordability stress test and revaluation, which is handy if rents are tight against the ICR. The catch is you cannot raise extra borrowing and you are limited to that lender's own deals, so you may leave a better rate on the table. If releasing equity is the goal, a full remortgage to a new lender is the route, and the stress test applies in full.
A quick pre-flight checklist
- Confirm your current balance and ERC-free date.
- Get a realistic valuation, not an optimistic one, and work out your LTV band.
- Model the rent against 125% and 145% ICR at a 5.5% stress rate.
- Decide: equity release (full remortgage) or rate-only (product transfer).
- Start four to five months before your fix ends.
This is general information, not tax or financial advice. Your position depends on your tax band, the lender's criteria on the day, and your own plans, so speak to a whole-of-market broker before you commit.
Remortgaging in 2026 is less about chasing the headline rate and more about whether the rent clears a stricter stress test and whether the timing dodges the early repayment charge. Do that maths first, and the equity release either falls out naturally or tells you honestly that this is a rate-switch year, not a cash-out one.
