Lender small print, sourced and dated
TSB: the mortgage dates and limits that cost money
These are the TSB rules that decide when overpaying is free, when leaving is cheaper, and how early your next deal can be locked. Every figure links to the lender's own published page with the date we last checked it — and where their public pages don't confirm a detail, we say so instead of guessing.
| Penalty-free overpayment allowance | 10% of the amount owed at 1 January, each calendar year · TSB's published policy, checked 2026-08-15 |
|---|---|
| Early-lock (product transfer) window | Not verified — across the market, 3 to 6 months is typical. |
| Overpaying beyond the allowance | The excess is normally charged at your deal's early repayment charge rate — the percentages and step-down dates are in your mortgage offer. |
| Not confirmed by TSB's public pages | early-lock window. We show the market assumption for these rather than invent a figure. |
Turn the rules into your dates
Rules only save money on the days they apply to your own deal: the day the allowance resets, the day the charge steps down, the day the lock window opens. Work out your remaining TSB allowance free, or build your full timeline in two minutes. A watch then emails you before each date — £7.99, once, no commission from TSB or anyone else.
Frequently asked questions
How much can I overpay on a TSB mortgage without a charge?
TSB's published rule is 10% of the amount owed at 1 January, each calendar year. Overpayments beyond that are usually charged at your deal's early repayment charge rate. Your own offer document is the definitive statement.
When does the TSB overpayment allowance reset?
It resets each calendar year. Unused allowance does not carry over.
How early can I lock a new deal with TSB?
We have not verified TSB's own window; across the market, existing-customer switches typically open 3 to 6 months before the deal ends, and offers from other lenders generally last up to 6 months.
WatchMyMortgage is independent and takes no commission from TSB or any lender. Rules summarised from the linked public pages on the dates shown; lenders change terms, and your mortgage offer is the definitive statement of yours. This is information, not financial advice; for advice on your circumstances, speak to a mortgage adviser regulated by the FCA.