Purposive four-issuer sample of public pages; not representative or exhaustive; no ranking. Original scenarios are synthetic budgets, not customers or market statistics.
Commercial status: There are no affiliate links in this edition. No issuer paid for inclusion or approved the sample; attribution and links are optional.
A longer interest-free period offers more time, not necessarily a lower fee. This balance-transfer cost benchmark compares four selected UK issuer disclosures checked on 15 October 2026, then shows the funding budget for an invented £3,000 transfer. It is a reproducible small sample, not a market ranking.
The distinction matters before the arithmetic. An advertised maximum period is not an individual offer. And a funding budget is not a card statement: our calculations reserve the fee separately and divide only the transferred principal. They do not simulate fee interest, payment allocation or what happens after a promotion expires.
What the selected disclosures establish
We selected four issuers to make the fee-versus-time comparison inspectable, including a shorter fee-free offer. We did not search every lender, select by approval odds or test actual applications. There is no claim that the sample is representative, cheapest or suitable for a particular borrower.
| Selected product | Advertised 0% transfer period | Transfer fee |
|---|---|---|
| TSB Platinum | Up to 38 months | 3.49% within 90 days |
| HSBC Balance Transfer | Up to 36 months | 3.09%, minimum £5, within 60 days |
| Santander Everyday Long Term | 34 months from opening | 3.15%, minimum £5 |
| NatWest Balance Transfer | Up to 11 months from opening | No transfer fee; transfer within first three months |
The documents expose different clocks and alternatives. TSB's summary gives 38, 35 or 32 months from opening and explicitly includes the transfer fee at the promotional rate. HSBC's summary starts its transfer promotion on the transfer date and lists a shorter possible offer. NatWest specifies an individual range of nine to eleven months. Santander's clock starts at opening. Delaying a transfer can therefore change the usable time.
Older document dates are preserved in the raw evidence. TSB's summary is dated March 2026; Santander's linked filename refers to October 2025. Reopening those documents today establishes what the current pages link to, not a new product announcement today. An individual agreement may differ and remains the controlling evidence.
Two horizons, not one league table
For each selected product, the downloadable model calculates a six-month principal-clearance budget and a second path using its advertised maximum period. All eight scenarios assume an immediate eligible transfer, no new purchases, no defaults and no interest on the transferred principal during that horizon.
The fee is calculated in integer pence, rounded half-up, with any stated minimum applied. We reserve that amount at the outset instead of assuming it shares a promotional rate. The monthly principal target is £3,000 divided by the chosen number of months, rounded upwards to a penny. The last target is reduced to the remaining principal.
These are funding targets, not lender minimum payments or a promise that a first payment clears a particular fee. The actual fee posting date, interest and allocation must be checked. Any such additional charge is outside the outputs. A borrower must still meet the statement's contractual requirements.
Read the fee beside the monthly target
Original illustrative results: a £3,000 transfer produces fee budgets of £104.70 for TSB, £92.70 for HSBC, £94.50 for Santander and £0 for the selected NatWest card. On the common six-month horizon, each principal target is £500 monthly. The total principal-plus-fee budgets are £3,104.70, £3,092.70, £3,094.50 and £3,000 respectively, excluding any unmodelled charges.
Using maximum periods instead, principal targets are £78.95 over 38 months, £83.34 over 36, £88.24 over 34 and £272.73 over eleven. Final payments are smaller where rounding requires it. These differing horizons cannot establish which offer is cheaper over the same time. They show how much monthly principal clearance the assumed timetable demands.
A shorter individual offer changes the answer. If the NatWest period were nine months, £3,000 would require a £333.34 monthly principal target, with a smaller final payment. That is a scenario, not evidence of what any applicant will receive. If that target does not fit, a zero fee has not resolved the repayment problem.
Reproduce the result and inspect the omissions
Download the full evidence and limitations, numeric input table, eight scenario outputs, dependency-free calculation module and method and reproduction instructions. No personal details are needed. The method uses no network connection or tracking.
Separate Python Decimal calculations reproduced twelve cases, including fee minimums, half-penny rounding and a one-penny balance. JavaScript tests compare exact penny outputs and reject invalid inputs. This is an automated recalculation by the same operator, not an independent human audit or validation by the issuers.
MoneyHelper and HSBC's explanatory guidance both emphasise fees, promotional expiry and repayment planning. MoneyHelper also cautions against assuming another transfer will be available. Accordingly, this benchmark does not count refinancing as repayment or estimate savings against an old card whose actual rate is unknown.
Use the table to choose which documents to investigate, not which application to submit. Save your actual transfer amount, accepted fee, exact end date and repeatable payment beside the downloaded method. If any consequential term is missing—or the reliable payment leaves a balance at expiry—resolve that gap before treating the headline period as an answer.
From comparison to calculation
Check the terms in the offer you actually receive.
Credit Over Debt’s Offer X-Ray compares the amount financed, fees, payment schedule and modeled cost using the figures you enter.
Open the free toolkitPrimary sources and product pages
- TSB: Platinum Balance Transfer Card — current product page (checked 2026-10-15)
- TSB: Platinum Balance Transfer Card — linked summary disclosure (checked 2026-10-15)
- HSBC UK: Balance Transfer Credit Card — current product page (checked 2026-10-15)
- HSBC UK: Balance Transfer Credit Card — linked summary disclosure (checked 2026-10-15)
- Santander UK: Everyday Long Term Balance Transfer Credit Card — current product page (checked 2026-10-15)
- Santander UK: Everyday Long Term Balance Transfer Credit Card — linked summary disclosure (checked 2026-10-15)
- NatWest: Balance Transfer credit card (no transfer fee) — current product page (checked 2026-10-15)
- NatWest: Balance Transfer credit card (no transfer fee) — linked summary disclosure (checked 2026-10-15)
- MoneyHelper: Transferring your credit card balance (checked 2026-10-15)
- HSBC UK: What is a balance transfer credit card? (checked 2026-10-15)
Product details last checked Oct 15, 2026; next scheduled review Oct 22, 2026. This UK-focused guide is educational information, not individualized financial, legal or tax advice. Product terms, offers and eligibility can change.