Remortgage Calculator

The decision homeowners make every 2-5 years

Mortgages typically fix rates for 2, 5, or 10 years. When the fixed period ends, your deal reverts to the lender's Standard Variable Rate (SVR) — usually 2-4 percentage points higher than your fixed rate. Remortgaging means switching to a new fixed deal (with your current lender or a different one) to avoid the SVR jump. This is one of the most consequential recurring financial decisions in homeownership, often worth tens of thousands across the life of the mortgage. The calculator above compares your options; the commentary below is about what to actually do with the comparison.

The SVR trap and why it exists

Lenders love SVR customers. When your 2-year fix ends, the default is the lender's SVR — which might be 2-4 percentage points above current market rates for a comparable new fix. On a 200,000 mortgage, SVR at 7.5% vs a new fix at 4.5% is roughly 350 more per month (4,200/year). Multiply across millions of borrowers, and SVR becomes highly profitable for lenders — and correspondingly expensive for borrowers who don't actively remortgage. Never stay on SVR if you can avoid it. The lender benefits from your inertia; remortgaging breaks the trap.

The 3-month remortgage window

You can typically apply for a remortgage 3-6 months before your current fix ends. Rate offers from most lenders are valid for 3-6 months, so applying early locks in a rate without triggering an immediate switch. This is particularly valuable when rates are expected to move: you lock in at the current rate and if rates drop before your new deal starts, you can usually switch to a better product then; if rates rise, you're protected by the rate you locked. Not applying until the last moment means accepting whatever rate is available at that precise point, which is worse regardless of direction.

The cost structure of remortgaging

Remortgage costs vary substantially. Major components:

Arrangement fee: 0-2,000. Some products offer fee-free alternatives with slightly higher rates — worth comparing total cost over the deal period.

Valuation fee: 200-500, sometimes free as a product benefit.

Legal fees: 200-500 for straightforward remortgages, sometimes free on certain products. Higher if switching lender or with complex circumstances.

Early repayment charge on existing deal: Only applies if remortgaging before the fixed period ends. Typically 1-5% of outstanding balance. Usually prohibitive to pay unless you're definitely saving enough to justify.

Mortgage broker fee: 300-700 if using a fee-charging broker. Many brokers are fee-free (earning commission from lenders).

Total costs typically 500-3,000. The remortgage benefit needs to clear these within the new fixed period to be worthwhile.

Fee vs rate trade-off

A common dilemma: product A offers 4.3% with a 1,995 arrangement fee; product B offers 4.7% with no fee. Which wins? Depends on mortgage size and deal length. On a 300,000 5-year fix: product A saves 0.4% × 300,000 × 5 ≈ 6,000 in interest over the deal period, but costs 1,995 in fee. Net saving ≈ 4,000, so A wins. On a 100,000 5-year fix: 0.4% × 100,000 × 5 ≈ 2,000 in interest saving vs 1,995 fee. Net saving ≈ 5 — essentially a wash, so B (simpler) wins. The break-even balance is around 125,000 for a 0.4% rate difference with a 1,995 fee. Below that, fee-free products usually win; above it, fee-charging lower-rate products often win.

Fixed for 2, 5, or 10 years?

The fix length is as important as the rate. Trade-offs:

2-year fix: Lowest typical rate but most frequent remortgaging (fees, hassle, rate exposure). Best when expecting rates to fall.

5-year fix: Middle ground; most popular choice. Rate typically 0.1-0.3% above 2-year but locks certainty for longer. Usually best default.

10-year fix: Rate premium of 0.3-0.7% above 5-year but maximum stability. Best when expecting rates to rise or wanting to eliminate rate uncertainty. Exit flexibility is limited — early exit charges often severe.

For most homeowners with stable circumstances, 5-year fix balances cost and certainty. The 2-year fix can outperform in specific rate environments but adds remortgaging hassle. The 10-year fix is rarely optimal but appeals to those who place high value on certainty.

Switch lender or stay with current?

Staying with current lender is typically simpler (no full application process, often just a rate-switch form) but may not get the best rate. Switching lender involves a full application including credit check and valuation, but can secure better rates. Rule of thumb: if the best external rate is 0.2%+ below your lender's retention offer, switching is usually worthwhile despite the admin. If the gap is smaller, staying is usually right. Mortgage brokers can check both simultaneously — worth using for significant mortgages.

The loan-to-value tier effect

Your LTV at remortgage determines available rates, and LTV has likely improved since your last remortgage (both through paying down principal and through property appreciation). Moving from 85% LTV to 75% LTV unlocks rates typically 0.3-0.7% better. From 75% to 60% LTV, another 0.1-0.3% improvement. Check your current LTV before remortgaging — you might qualify for better rate tiers than your last deal provided.

Remortgaging when circumstances have changed

Negative changes since last mortgage (income drop, job change, new debt) can cost approval. Positive changes (income rise, debts cleared, additional deposit available through house value gain) can secure better rates. Borrowers who've paid down debt, increased savings, or had income rise meaningfully since last remortgage should specifically ask about "enhanced multiplier" or "professional" rates that weren't available before. These aren't automatically offered; they're available when asked.

When early exit applies

Generally, paying early exit charges is a bad bet — they're specifically designed to make early exit uneconomic. But there are narrow cases where it works: rate drops dramatically between your fixing and current environment (the gap between your rate and new deals exceeds the ERC over the fixed period remaining), circumstances changed making your current product unsuitable (moving, separation, substantial windfall), or you're selling the property anyway. Run the numbers carefully — the ERC amount multiplied across the remaining fixed period often dominates, meaning early exit is rarely worthwhile.

What this calculator shows

The tool compares your current mortgage payment with a proposed remortgage deal, factoring in rate, fees, and deal length. It doesn't automatically model the post-fixed-period situation (SVR or next remortgage), early repayment charges, or specific lender approval criteria. Use the output as the comparison baseline; add the other factors for a complete decision.