The warning visible in UK wholesale markets at the beginning of September is now feeding directly into mainstream mortgage pricing. HSBC and Nationwide are increasing rates from 15 September, while Santander is raising selected products by as much as 45 basis points from 16 September.
For Willow's residential and high-value borrowers, that is the important development. On 3 September we wrote that higher wholesale funding costs could make a £1m-plus remortgage a timing decision again. The market has since moved from the risk of lender repricing to widespread increases from some of the UK's biggest mortgage providers.
Mortgage Solutions reported on 14 September that Santander is increasing selected rates by as much as 45 basis points. Nationwide is lifting fixed rates by as much as 30 basis points across first-time buyer, home mover, remortgage, switcher and additional-borrowing ranges. HSBC's changes cover a wide range of residential lending, including two- and five-year fixed rates and two-year trackers across every LTV band, with Premier and High Value Mortgage products included.
At almost the same time, the market's view of Bank Rate has shifted. Reuters reported on 14 September that Goldman Sachs now expects a 0.25 percentage-point increase in November, while Citigroup expects one increase later in 2026 and another in early 2027, probably in November and February. LSEG data cited by Reuters showed traders pricing around 47 basis points of Bank of England tightening by the end of 2026.
What Has Changed Since Willow's 3 September Warning?
Mainstream mortgage rates are now being repriced materially higher. HSBC and Nationwide changes take effect on 15 September; Santander's latest increases take effect on 16 September, with selected Santander rates rising by as much as 45 basis points.
The policy-rate debate has moved as well. Goldman Sachs and Citigroup both moved away from their previous expectation that Bank Rate would remain unchanged through 2026, although Goldman still expects no change at the Bank of England's 17 September meeting.
This does not prove mortgage rates will keep rising. It does mean borrowers who were waiting on the assumption that pricing could only improve now have a different risk to assess.
A 45-Basis-Point Move Is Not Small on a Seven-Figure Mortgage
Mortgage-rate headlines can make a move of 0.20, 0.30 or 0.45 percentage points sound marginal. On a large balance, it is not. Forty-five basis points means 0.45 percentage points. Applied to a £1m balance for one year, that is approximately £4,500 of additional interest before allowing for capital repayments, changing balances, fees or any difference in product structure.
On £2m, the same simplified calculation is £9,000 a year. On £5m, it is £22,500. That does not mean every borrower will see a 45-basis-point rise, or that the Santander increase represents the whole market. It illustrates why apparently small changes in mortgage pricing can alter the commercial decision for high-value borrowers.
The same principle applies when the increase is 30 basis points. A 0.30 percentage-point difference on a £1m balance equates to around £3,000 of interest over a year on a simple interest-only illustration. For borrowers choosing between acting now and waiting several months, the potential cost of further repricing should be weighed against the possibility that rates later improve.
The Question Is Not: “Will Rates Definitely Rise Again?”
The more useful question is: what refinancing or purchase position could be secured now, what flexibility would remain if rates later improve, and how much repricing risk is the borrower comfortable leaving open?
The Bank of England Does Not Need to Raise Rates for Fixed Mortgages to Move Higher
The next Monetary Policy Committee decision is scheduled for 17 September. The Bank of England currently lists Bank Rate at 3.75%, and Goldman Sachs expects it to remain there at this week's meeting.
Borrowers should not infer from that expectation that fixed mortgage pricing will necessarily remain stable. Lenders price fixed mortgages using their own funding position and wholesale market rates that reflect expectations for future interest rates. When those expectations rise, mortgage pricing can move before Bank Rate changes — or even if the MPC ultimately holds.
That distinction was central to Willow's early-September analysis. Wholesale funding costs had already risen sharply before the current round of mainstream repricing. The subsequent lender changes demonstrate why a borrower can face higher fixed rates without waiting for an MPC vote.
There was already a tightening debate inside the Bank. At its July meeting, the MPC voted 6–3 to maintain Bank Rate at 3.75%, with three members preferring an increase to 4%. The new Goldman and Citigroup forecasts do not determine what the MPC will do; they show that external expectations about the path beyond September have changed.
For Remortgagers, Waiting Has Become a More Active Decision
A borrower whose existing fixed rate ends in six or nine months may still decide that waiting is appropriate. There may be an early repayment charge, a future property sale, an expected reduction in the mortgage balance or reasons to believe that a different lending structure will become available later.
What has changed is the case for leaving the entire refinancing position unexamined. If a viable mortgage can be secured several months before the existing deal ends, the borrower may be able to protect against further repricing while continuing to monitor the market. Offer validity and the ability to change product before completion vary by lender, so that flexibility must be checked rather than assumed.
For a high-value borrower, the comparison should also extend beyond the automatic product transfer offered by the existing provider. A £1m, £2m or £5m refinance can fall within the appetite of mainstream large-loan lenders, specialist banks and, in appropriate circumstances, private banks. The appropriate route can change depending on LTV, income structure, assets, interest-only requirements and the intended repayment strategy.
A Mortgage Maturity in the Next Nine Months Is Now Worth Reviewing
There is no universal point at which every borrower should submit a remortgage application. The correct timing depends on the current mortgage, available rates, lender offer period, early repayment charges and the borrower's wider plans. However, the current repricing means a maturity in the coming months is no longer an event that should automatically be left until the final weeks.
For clients who have been deliberately waiting for lower rates, the appropriate next step is not necessarily to abandon that view. It is to benchmark it. Knowing the cost and structure available now creates a reference point against which the decision to wait can be measured.
Homebuyers With an AIP Should Recheck the Actual Product
The repricing is also relevant to buyers already in a transaction. An agreement in principle obtained several weeks ago demonstrates that a lender may be willing to consider the borrower based on information supplied at that stage; it should not be treated as proof that the mortgage product originally discussed is still available at the same price.
For a buyer approaching exchange without a full mortgage offer, the financing position should therefore be checked against the current product range. This becomes particularly important where affordability was already tight, because a higher rate can affect both monthly cost and the amount a lender is prepared to advance.
That does not mean a buyer should rush into an unsuitable product simply because rates have risen. It means the financing should be made executable before the legal timetable removes the opportunity to compare alternatives.
High-Value Borrowers Should Compare More Than the Headline Rate
The largest mainstream lenders can be highly competitive on seven-figure mortgages, but headline pricing is only one part of the decision. Product fees, interest-only availability, maximum loan size, treatment of bonus or investment income, age, future liquidity and the property itself can materially change the outcome.
HSBC's latest changes are particularly relevant to this segment because Mortgage Solutions reports increases across its Premier and High Value Mortgage ranges as well as standard residential products. For existing high-value borrowers, that is a reminder not to assume that relationship status insulates a mortgage from broader funding-market changes.
Private-bank lending can also be relevant where the mortgage needs to be assessed alongside a wider balance sheet, but it should not be used simply because the loan is large. Some clients will be better served by a mainstream large-loan product; others need a specialist or private-bank structure. The task is to compare the available routes against the actual borrower rather than choose the lender category first.
| Borrower Position | What to Establish Now |
|---|---|
| Fixed rate expiring | Current refinance options, offer validity, early repayment charge and the cost of reverting to the lender's follow-on rate. |
| AIP but no application | Whether the intended product remains available and whether revised pricing changes affordability or loan size. |
| Purchase approaching exchange | A full executable finance route rather than relying on an earlier indication of borrowing capacity. |
| Existing lender renewal | How the product-transfer offer compares with the wider large-loan, specialist and private-bank market. |
| Capital raising | Whether the additional debt changes the optimal lender, repayment basis or security structure. |
What If Mortgage Rates Fall Again?
That possibility is precisely why the strategy should not be framed as a prediction. Wholesale markets can reverse quickly. Energy prices can change, inflation data can surprise in either direction and lenders can cut pricing to compete for business even before the Bank of England changes Bank Rate.
Securing an acceptable mortgage position early is therefore not the same thing as declaring that today's rate will be the lowest available before completion. Depending on the lender and stage of the case, it may be possible to review or switch to a cheaper product before the mortgage completes. The rules vary and should be confirmed for the actual application.
The useful objective is optionality: protect the transaction against a worse outcome where possible while retaining as much flexibility as the lender permits if the market becomes more favourable.
How Willow Private Finance Can Help
Willow Private Finance can review residential purchases and remortgages before the current deal or transaction timetable forces a decision. For larger balances, we compare relevant mainstream large-loan lenders, specialist banks and private-bank routes rather than assuming that the existing provider or the lender with the lowest advertised rate is automatically the best fit.
The review can include fixed versus tracker options, interest-only structures, capital raising, complex income, future liquidity events and the flexibility available between mortgage offer and completion. Where a client already has an AIP or recommendation, we can assess whether the current repricing changes the case for proceeding.
The message is not that Bank Rate is certain to rise in November, or that mortgage rates cannot fall again. It is that the market has already repriced enough to make waiting a decision with a measurable cost and risk. For a £1m-plus borrower, establishing the viable position now can be more useful than trying to make a perfect forecast.
Remortgaging in the Next Nine Months? Establish What You Can Secure Before the Next Repricing.
HSBC and Nationwide have moved rates higher and Santander is following. On a seven-figure balance, even a small change in pricing can materially alter the annual cost.
Willow Private Finance can compare mainstream large-loan, specialist-bank and private-bank options now, while continuing to monitor whether a better route becomes available before completion.
Explore Residential Mortgages →Frequently Asked Questions
Key questions for borrowers deciding whether recent mortgage repricing should change their purchase or remortgage timetable.
Should I secure a remortgage now if my fixed rate ends in the next six to nine months?
It can be sensible to establish what can be secured now rather than relying on a rate forecast. The appropriate timing depends on the lender's offer validity, any early repayment charge, the mortgage balance, loan-to-value, income and whether the lender allows a product change before completion if pricing improves.
Does a Bank of England rate hold mean fixed mortgage rates should stop rising?
No. Fixed mortgage pricing is influenced by wholesale funding costs and market expectations for future interest rates, not only the Bank Rate in force on the day. Mortgage lenders can therefore increase or reduce fixed rates even when the Bank of England leaves Bank Rate unchanged.
How much does a 45-basis-point mortgage rate increase cost on £1m?
As a simplified interest-only illustration, 45 basis points is 0.45 percentage points. Applied to a £1m balance for one year, that is approximately £4,500 of additional interest. On £2m, the equivalent is approximately £9,000. Actual costs depend on the repayment basis, balance, fees and mortgage terms.
Does an agreement in principle protect the mortgage rate I saw earlier?
An agreement in principle should not be treated as evidence that the same mortgage product or rate will remain available when a full application is submitted. Product availability and reservation processes vary by lender, so buyers approaching exchange should confirm the current financing position.
Should a £1m-plus borrower only compare mainstream mortgage lenders?
Not necessarily. Depending on the borrower, property, income, assets, repayment strategy and loan size, the relevant market can include mainstream large-loan lenders, specialist banks and private banks. Comparing the complete facility can be more useful than assuming the existing lender's renewal terms are automatically the best fit.