How to Pay Off Debt Fast: Every Strategy Ranked by What It Actually Saves
We simulated the standard advice month by month on a realistic UK debt mix, instead of repeating it. Some of it is worth thousands. Some of it is worth almost nothing.
Every article about paying off debt fast gives you the same list: pay more than the minimum, do a balance transfer, consolidate, use windfalls, cancel subscriptions. What none of them tell you is what each of those moves is actually worth in pounds — so you cannot tell the strategy that saves thousands from the one that saves the price of a coffee.
So we measured them. We took one realistic UK debt mix and ran every strategy through a month-by-month simulation, the same way we tested the snowball and avalanche methods. Same debts, same starting point, one change at a time.
The reference debts
£15,000 across four debts, with £350 a month of minimum payments — the shape UK debt usually takes, where the smallest debts carry the highest rates:
| Debt | Balance | Rate | Minimum |
|---|---|---|---|
| Store card | £1,200 | 34.9% APR | £30 |
| Overdraft | £1,500 | 39.9% EAR | £40 |
| Credit card | £4,800 | 24.9% APR | £120 |
| Personal loan | £7,500 | 9.9% APR | £160 |
One result before any strategy: paying only the minimums never clears these debts. The overdraft's interest at 39.9% EAR is £42.56 a month on a £1,500 balance — more than its £40 minimum payment — so the balance rises every month you fail to overpay it. This is not a rigged example; interest outrunning the minimum is exactly how the minimum payment trap works, and overdrafts and store cards are where it bites hardest.
The ranking: what each move is worth
Baseline: minimums plus £100 a month extra, cleared debts' payments rolling forward. That gets you debt-free in 45 months with £5,068 of interest. Each strategy below changes one thing:
| Strategy | Interest saved | Months sooner |
|---|---|---|
| First £50/month extra (vs paying no extra at all) | £4,647 | 21 |
| Balance transfer the credit card to 0% (24 months, 3% fee) | £2,346 net of the fee | 5 |
| Consolidate the three expensive debts at 12.9% | £2,242 | 5 |
| Increase the extra from £100 to £250/month | £1,984 | 14 |
| £500 windfall paid straight in at month one | £679 | 3 |
| Talk the card down from 24.9% to 19.9% | £670 | 1 |
| Switching snowball to avalanche order | £30 | 0 |
Each row simulated month by month on the reference debts. The first row compares £50 extra against minimums-only with rollover; other rows compare against the £100-extra baseline.
Two things stand out. The famous strategies people argue about — snowball versus avalanche — sit at the bottom of the table. And the unglamorous one, finding more money each month, sits at the top.
1. The first £50 a month is worth more than everything else
Here is the full progression, minimums plus a growing extra payment:
| Extra per month | Debt-free in | Total interest | Saving vs previous row |
|---|---|---|---|
| £0 (minimums, rolling forward) | 76 months | £11,412 | — |
| £50 | 55 months | £6,765 | £4,647 |
| £100 | 45 months | £5,068 | £1,697 |
| £250 | 31 months | £3,084 | £1,984 (for £150 more) |
The returns diminish as you go. The first £50 saves £4,647; the second £50 saves £1,697; beyond that each £50 is worth roughly £660. The reason is simple: every extra pound shortens the time the expensive debts exist, and the earliest pounds shorten it most. If you can only find one small change, find the first £50 — cancelled subscriptions, one fewer takeaway a week, selling something. It outperforms every clever financial product on this list.
2. Balance transfers: the best rate fix, with two conditions
Moving the £4,800 credit card to a 24-month 0% card with a typical 3% fee costs £144 up front and saves £2,490 of interest — £2,346 net, and debt-free five months sooner. Per pound of effort it is the strongest rate-side move available, because it takes the largest expensive balance to zero percent rather than shaving a few points.
The two conditions: do not spend on the new card (purchase rates on transfer cards are poor, and new spending usually is not covered by the 0% deal), and know the end date — our simulation cleared the transferred balance within the 24 months, but a balance still there when the promotional rate ends reverts to a standard APR. Acceptance and the fee depend on your credit record; a shorter 0% window with a lower fee often beats a longer window with a higher one if you will clear it in time anyway.
3. Consolidation: works if the total payment stays the same
Rolling the store card, overdraft and credit card (£7,500 at rates from 24.9% to 39.9%) into a single 12.9% personal loan saved £2,242 in our simulation — but only because we kept paying the same £450 total each month, using the loan's lower required payment to overpay elsewhere.
That caveat is the whole game. Consolidation loans advertise a lower monthly payment over a longer term, and if you take the five-year term at the minimum and absorb the difference into spending, you can end up paying more interest than you started with, at a lower rate. The loan does not get you out of debt faster; the unchanged monthly total does. Consolidation also usually means closing the cleared cards — leave them open with balances at zero and the temptation, and you can end up with the loan and new card debt.
4. Windfalls and phone calls: real but smaller than advertised
A £500 bonus or tax refund paid straight into the priority debt at month one saves £679 and three months. Worth doing without hesitation — the earlier it lands, the more it saves — but note it saves less than finding £50 a month, because it happens once and the monthly extra happens fifty times.
Ringing your card provider and negotiating 24.9% down to 19.9% saves £670. That is a good return on a ten-minute phone call, and lenders do agree to this more often than people expect, particularly for long-standing customers who have never missed a payment. But it is a supporting move, not a strategy: five points off a rate is worth a third of what taking that balance to 0% is worth.
5. The things that do not show up in the maths
Three standard pieces of advice do not move the simulation at all, and we are listing them anyway, because they decide whether you follow through:
- A small emergency fund first. £500 held back looks inefficient next to 39.9% debt, but without it the first car repair goes straight back on the card and undoes months of progress. Its value is that it keeps the plan alive, which no interest calculation captures.
- Automate the extra payment on payday. The plan above only works if the £100 actually leaves your account every month for 45 months. A standing order does not have motivated and unmotivated weeks.
- Track the balance monthly. Watching £15,000 become £13,800 then £12,500 is what month-thirty discipline runs on.
What about snowball vs avalanche?
The method question gets most of the attention and matters least. On these exact debts the avalanche saved £30 over 31 months compared with the snowball, because in the UK the small debts are usually the expensive ones, so both methods attack them in nearly the same order. We covered this in detail, including when the avalanche genuinely wins, in our snowball vs avalanche comparison. Pick the one you will stick to; spend your energy on the rows at the top of the table.
A plan you can start this month
- List every debt — balance, rate, minimum. Include overdrafts, store cards and buy-now-pay-later, not just cards and loans.
- Check whether any minimum fails to cover its interest (overdrafts especially). Those debts are growing and go to the front of the queue regardless of method.
- Find your first £50 a month and set up a standing order for it on payday.
- If you have card debt at 20%+ and a reasonable credit record, price up a 0% balance transfer. Do the sums net of the fee.
- Pick snowball or avalanche, point all the extra at one debt, and roll each cleared minimum into the next.
- Put your real numbers into the debt payoff calculator and write down the debt-free date it gives you. Re-run it whenever anything changes.
Frequently asked questions
What is the single fastest way to pay off debt?
Increasing the amount you pay each month, and the first extra money matters most. On our simulated 15,000 pound UK debt mix, going from paying minimums to adding 50 pounds a month saved 4,647 pounds in interest and 21 months. The second 50 pounds saved 1,697 pounds. Rate fixes like balance transfers come next, and everything else is smaller than people expect.
Is a balance transfer worth the fee?
Usually, yes, if you have high-rate card debt and can get accepted. Moving a 4,800 pound credit card balance at 24.9% APR to a 24-month 0% card with a 3% fee cost 144 pounds up front and saved 2,490 pounds of interest in our simulation, a net gain of about 2,346 pounds. The two conditions are that you do not spend on the new card and that you have a plan for when the 0% period ends.
Does debt consolidation speed things up?
It can, if the loan rate is genuinely lower and you keep paying the same total amount each month. Consolidating a store card, overdraft and credit card at a blended 28% or so into a 12.9% loan saved 2,242 pounds in our simulation. The trap is treating the lower monthly minimum as the new normal: stretch the same debt over five years at the minimum and the saving shrinks or disappears.
How much difference does an extra 50 pounds a month really make?
On our reference debts, 4,647 pounds and 21 months, which is more than any other single change we tested. The catch is diminishing returns: each additional 50 pounds saves less than the one before, because the debt is gone sooner and there is less interest left to avoid.
Should I use the snowball or avalanche method to pay off debt faster?
It matters far less than how much you pay. On this same debt mix the avalanche beat the snowball by 30 pounds over 31 months, because in the UK the smallest debts are usually also the most expensive ones, so both methods end up in nearly the same order. Pick whichever you will stick to and put your energy into the payment amount instead.
Run it on your own debts
Every figure above is one debt profile. Yours will differ — the ranking usually holds, but the amounts are yours alone. The debt payoff calculator shows your payoff date and total interest, and lets you test what an extra £50 or £100 a month does to both. For the bigger picture, including when to get free debt advice rather than optimise repayments, see getting out of debt in the UK.
Method, assumptions and help
All figures were simulated month by month in code rather than estimated. Interest is applied monthly at (1 + APR)1/12− 1, then payments: minimums to every live debt, then all remaining capacity to the priority debt (smallest balance first), with cleared debts' payments rolling forward. Minimum payments are held constant rather than declining with the balance, a simplification that slightly shortens all scenarios equally. The balance transfer assumes a 3% fee added to the transferred balance, 0% for 24 months, 24.9% thereafter. The consolidation assumes a 12.9% APR loan over five years with the total monthly budget unchanged. Rates and balances are illustrative of common UK products, not published averages, and lender acceptance is never guaranteed.
SnowballCalc is published by CJ Software Ltd. This page is general information, not debt advice. If your minimums are unaffordable or you are borrowing to cover essentials, skip the optimisation and get free, impartial help from StepChange, National Debtline or Citizens Advice. Last reviewed August 2026.