Buy-to-let fixed rates are rising again. Moneyfacts put the average two-year buy-to-let fix at 5.32% and the five-year at 5.70% on 8 September 2026, and the Bank of England's decision on 17 September (a hold at 3.75%, but with three of nine members voting for a rise) makes further increases more likely than cuts in the months ahead. If your fixed deal ends in the next six months, the question is no longer whether to wait for cheaper rates, but how to lock in before they climb.
What are buy-to-let mortgage rates in September 2026?
The market averages moved up in the first week of September and lenders kept repricing after that:
| Moneyfacts average | 1 September 2026 | 8 September 2026 |
|---|---|---|
| Two-year fixed buy-to-let | 5.29% | 5.32% |
| Five-year fixed buy-to-let | 5.66% | 5.70% |
Source: Moneyfactscompare.co.uk, reported by Property118 on 8 September 2026. For comparison, the average residential two-year fix was 5.63% and the five-year 5.68% on 7 September (Moneyfacts).
Behind the averages, individual lenders moved faster. In early September HSBC raised buy-to-let rates by up to 0.16 percentage points, NatWest by 0.10 points (up to 0.25 through its intermediary arm), Coventry Building Society by up to 0.20 and Leek Building Society by up to 0.13. Family Building Society withdrew its fixed buy-to-let range, and CHL Mortgages and ModaMortgages pulled limited-edition deals. By 11 September, five more lenders had repriced fixed products upward in a single week.
Two things stand out. First, five-year fixes are clearly dearer than two-year fixes, because long-term borrowing costs have risen fastest. Second, this is a reversal: buy-to-let rates climbed in the spring after the Middle East conflict escalated at the end of February 2026, eased over the summer, and have now turned up again.
Why are rates rising when the Bank of England held?
Because fixed rates are priced off swap rates, which track where markets expect Bank Rate to go over the life of the fix, not where it is today. Those expectations have shifted sharply:
- Gilt yields jumped. In early September ten-year gilt yields went above 5.25%, the highest since August 2007, and by 11 September they had touched around 5.35%.
- Inflation is heading the wrong way. CPI was 3.1% in August, and the Bank expects it to rise to around 3.75% in the final quarter of 2026 and slightly above 4% in early 2027, driven by energy prices linked to the US and Iran conflict (Bank of England, September 2026).
- The economy is not weakening fast enough to offset it. UK GDP grew 0.4% in July, stronger than expected.
When swap rates rise, lenders reprice fixed deals within days, regardless of what the Bank does at its next meeting.
Will the Bank of England raise rates in November?
Markets think so. On 17 September the Monetary Policy Committee held Bank Rate at 3.75% by six votes to three, with Megan Greene, Catherine Mann and Huw Pill voting to raise it to 4%. The majority wanted more evidence that higher energy prices were feeding into wages and prices before moving, and said it "stands ready to act as necessary" to bring inflation back to the 2% target.
By 11 September, before that meeting, markets were fully pricing a November rise and four quarter-point increases by July 2027, which would take Bank Rate to 4.75% (Mortgage Professional Adviser). The next decision is on Thursday 5 November 2026, a week after the Budget on 28 October. Market pricing can be wrong, and much depends on energy prices, but it is what fixed rates are being built on today.
What does a 0.25-point rise cost a landlord?
About £500 a year for every £200,000 of interest-only borrowing. Here is the arithmetic on a £200,000 interest-only buy-to-let loan:
| Rate | Annual interest | Monthly interest |
|---|---|---|
| 2.50% (a typical 2021 fix) | £5,000 | £417 |
| 5.32% (today's two-year average) | £10,640 | £887 |
| 5.57% (plus 0.25 points) | £11,140 | £928 |
| 6.32% (plus 1 point, four rises) | £12,640 | £1,053 |
Each quarter-point adds £500 a year, or about £42 a month. If you hold personally, Section 24 gives you only a 20% tax credit on mortgage interest (22% from April 2027), so every extra £500 of interest costs you roughly £400 after tax whatever your tax band (Section 24 explained). A company paying 25% corporation tax bears about £375.
The quarter-points are not the real shock, though. Coming off a 2.5% fix taken in 2021 onto today's 5.32% adds £5,640 a year on the same £200,000 loan, which is more than £470 a month. If you are on a tracker, each Bank Rate rise passes through immediately: four rises would add £2,000 a year.
Will your remortgage pass the stress test?
This is where the choice between two and five years matters most. Lenders size buy-to-let loans on a stressed rate multiplied by an interest cover ratio (ICR), typically 125% for basic-rate taxpayers and companies and 145% for higher-rate taxpayers. Two-year fixes are usually stressed at the pay rate plus 2 points; five-year fixes are often stressed at the pay rate itself (the stress test explained).
Monthly rent needed to support a £200,000 loan at September 2026 average rates:
| Product | Stress rate | ICR 125% | ICR 145% |
|---|---|---|---|
| Two-year fix at 5.32% | 7.32% | £1,525 | £1,769 |
| Five-year fix at 5.70% | 5.70% | £1,188 | £1,378 |
A higher-rate landlord needs almost £400 a month less rent to pass on the five-year product, even though it costs 0.38 points more. For many remortgages that is the difference between borrowing what you need and having to put cash in. Criteria vary by lender, so check your own figures in the mortgage stress test calculator and see how ICR works.
Should I fix now or wait?
On current evidence, move early rather than wait. The reasoning:
- Book a rate before your deal ends. Most lenders let you secure a product three to six months ahead. If rates rise, you are protected. If they fall before completion, many lenders or brokers can switch you to a cheaper product. That asymmetry favours acting now.
- Look at a product transfer first. Moving to a new deal with your existing lender often avoids a fresh affordability and ICR assessment, which can rescue a remortgage that would fail the stress test elsewhere.
- Weigh five years against two. The five-year fix costs more per month today, but it passes the ICR on lower rent and covers the period in which markets expect rates to rise. A two-year fix is a bet that rates will be lower in 2028.
- Compare total cost, not headline rate. Percentage arrangement fees on a large loan can outweigh a 0.2-point rate difference over two years. Model it in the buy-to-let mortgage calculator.
- Do not drift onto the reversion rate. The average residential standard variable rate was 7.13% in early September, and buy-to-let reversion rates are often higher. On £200,000 interest-only, 7.13% is £14,260 a year, £2,860 more than a 5.70% fix.
Our guide to remortgaging a buy-to-let covers releasing equity and timing in more detail.
What does this mean for a landlord with 1 to 10 properties?
A margin squeeze, not a crisis. UK Finance counted 8,390 buy-to-let mortgages in arrears in the second quarter of 2026, 26% fewer than a year earlier (Property118), so the sector is not in distress. Rents are still rising too: the ONS put UK private rents up 3.8% in the year to August 2026, which helps the stress test. But the cheap-money cushion is gone, and each remortgage over the next year will reset your costs higher. List every fixed deal in your portfolio with its end date, start the process six months out, and model each property at today's rates plus one point so a November rise does not catch you out.
The same rates apply in Scotland and Wales; mortgage pricing is UK-wide.
This is general information, not financial advice. Mortgage rates change daily, so speak to a whole-of-market broker before you commit to a product.
