Should I always pick the mortgage with the lowest APRC?

Not always. APRC is a useful comparison metric, but it’s based on assumptions. If you know you will remortgage in two years, a two-year cost comparison may be more relevant.

Is cashback the same as a lower fee?

It can offset costs, but compare like-for-like. A £500 cashback can be valuable if it reduces your real upfront spend, but it doesn’t necessarily make a higher-fee mortgage cheaper overall.

What’s the biggest mistake people make?

Comparing headline rates without including fees and without defining a time horizon. The right mortgage depends on how long you expect to keep it and how sensitive you are to monthly payment changes.

Should I compare deals using monthly payment or total interest?

Use monthly payment to protect your budget. Use total interest (over a chosen horizon) to compare cost. Most people need both, because a deal can look affordable monthly but still be expensive over your planned time horizon.

Is a longer fixed period always safer?

A longer fixed period can provide payment stability, but it can reduce flexibility. If you might move, need to remortgage early, or plan large overpayments, early repayment charges and product rules can matter as much as the rate.

If I might move house, what should I prioritise?

Early repayment charges, portability (if relevant), and realistic exit plans. A deal that is slightly more expensive but easier to exit can be better if you expect to move during the fixed period.

Is it okay to add fees to the loan?

It can be, but it changes the total cost because you usually pay interest on the fee. If cash is tight, adding the fee can preserve buffer; if cash is comfortable, paying upfront can reduce long-run cost. Compare both scenarios.

How should I think about SVR in my budget?

Treat SVR as a “do not plan to stay here” placeholder. Many borrowers switch before reaching SVR or shortly after. For budgeting, it’s sensible to assume you will review options before the fixed period ends rather than relying on SVR being competitive.

What’s the simplest “good enough” comparison if I’m overwhelmed?

Pick a horizon (two or five years), then compare monthly payments, add fees to get a total cost over the horizon, and stress test payment at +1% and +2%. If one deal clearly wins across all three, that’s usually a strong signal.

Should I use a broker?

This guide can’t tell you what you should do, but brokers can be helpful when your income is complex, your case is time-sensitive, or you want help comparing eligibility and criteria across lenders.

What’s the main takeaway?

Define your time horizon, include fees, and stress test your budget. A slightly more expensive deal that fits your life and provides resilience can be better than a fragile “cheapest on paper” option.

How to compare mortgage deals (UK): rate vs fees, APRC, and break-even thinking

Why “lowest rate” is not always the cheapest mortgage

Mortgage comparison often gets reduced to “who has the lowest rate”. But the total cost of a mortgage deal can also be driven by:

product fees (arrangement/product fees)
incentives and cashback
the fixed period length
what rate you move to after the fixed period (often SVR unless you switch)

This guide shows a practical, defensible way to compare deals without pretending you can predict the future.

It is informational only.

Key terms (quick definitions)

The three comparisons you should make

1) Monthly payment comparison (short-term budget safety)

First, check: “can I afford this monthly payment comfortably?”

Use:

Mortgage repayment for quick payment estimates
Mortgage for full scenario modelling (price + deposit)

If Deal A is cheaper by £30/month but stretches your budget, it may be a false saving.

2) Total cost over your planned time horizon (the “keep the deal for X years” view)

Most people don’t keep the same mortgage deal for 25 years. They often:

remortgage when the fixed period ends
move house
overpay

So it’s often more realistic to compare cost over:

2 years (if comparing 2-year fixes)
5 years (if comparing 5-year fixes)

Use the Mortgage interest calculator to compare “interest paid in the first X years” as a planning estimate.

3) Fee vs rate trade-off (break-even thinking)

Fees are a one-off cost. Rate differences are a “per month” cost. Comparing them is a break-even problem:

If Deal A has a lower rate but higher fee, it only wins if you keep it long enough.
If you remortgage quickly, a low-fee deal may be cheaper overall.

A practical break-even method you can actually use

Here’s a simple method to compare two deals:

Pick your loan amount (the amount you’d borrow).
Pick your comparison horizon (e.g. 2 or 5 years).
Estimate monthly payment for each deal at its initial rate.
Add any upfront fees to the cheaper deal (or convert fees into an equivalent monthly cost).
Compare total cost over the horizon.

This isn’t perfect (real mortgages can calculate interest daily, and your rate can change), but it is far better than comparing headline rates alone.

Worked example: low rate + high fee vs higher rate + low fee

Assume:

Loan amount: £250,000
Term: 25 years
Horizon: 2 years

Deal A:

Rate: 4.80%
Fee: £1,999

Deal B:

Rate: 5.05%
Fee: £0

If Deal A saves you (say) £35/month versus Deal B, then over 24 months it saves about:

£35 × 24 = £840.

But Deal A’s fee is £1,999. In this simplified break-even view, Deal A would not “pay back” within 2 years.

If you keep the deal for longer, the rate saving has more time to accumulate — but if you plan to remortgage soon, fees matter a lot.

Costs people forget when comparing mortgages

Even if two deals have the same rate and fee, they can differ on practical costs and constraints.

Early repayment charges (ERCs)

Many fixed-rate products have ERCs during the fixed period. ERCs matter if you might:

move house
remortgage early
make large overpayments

The “cheapest” deal is not cheap if you can’t exit it when your life changes.

Valuation and legal costs (especially on remortgage)

Some remortgage deals include incentives (free valuation, free legal). Others do not.

If you are comparing remortgage deals, include:

valuation cost (if any)
legal fees (if any)
any admin costs

Overpayment flexibility

If you plan to overpay, check:

how much you can overpay each year without charge
whether the rules change during the fixed period

If you want to reduce interest, flexibility can matter more than a small rate difference.

A more realistic comparison: “total cost over 2 years” vs “total cost over 5 years”

A practical way to compare is to run the same two deals over different horizons:

2-year horizon: useful for 2-year fixes and for people likely to remortgage quickly
5-year horizon: useful for 5-year fixes and for people prioritising stability

Even if you can’t predict future rates, you can compare deals under the same assumptions and see which deal is sensitive to fees.

Break-even thinking (expanded)

Another way to think about fees is to convert them into an “equivalent monthly cost” across your horizon.

Example:

Fee: £1,999
Horizon: 24 months

Equivalent fee cost ≈ £1,999 ÷ 24 ≈ £83/month.

If the lower-rate deal only saves £35/month in payment, but costs an equivalent £83/month in fees, it is unlikely to win over 2 years.

Over 60 months, the equivalent fee cost is lower (~£33/month), so the lower-rate deal has more chance to win.

Rate changes after the fixed period (don’t ignore the “after”)

If you keep the mortgage beyond the fixed period, the follow-on rate matters.

Many borrowers move to a reversion rate (often SVR) unless they switch. Because SVR can be higher and can change, a sensible plan is:

assume you will review options before the fixed period ends
avoid planning a budget that only works if SVR stays low

A simple spreadsheet template (copy/paste structure)

You can use this structure for Deal A and Deal B:

Loan amount: £_____
Term (years): _____
Initial rate: _____%
Product fee: £_____
Fee paid upfront or added: (upfront/added)
Comparison horizon: _____ months
Estimated monthly payment: £_____
Total payments over horizon: £_____
Total fees over horizon: £_____
Total cost over horizon (payments + fees): £_____

Then add a “stress” row:

same deal, but rate +1% and +2% for payment comparison

The goal is to compare deals consistently, not perfectly.

APRC: what it is and how to use it

APRC is designed to help compare overall cost in a standardised way (including certain fees), but it uses assumptions about what happens after your initial deal period.

Practical use:

use APRC as a warning signal (e.g. “this deal has low initial rate but high overall cost assumptions”), and
still run your own “first 2/5 years” scenario comparisons.

Fixed period choice: 2-year vs 5-year (how to think about it)

This is not advice, but the trade-off often looks like:

2-year fixes: you refinance sooner (more admin and uncertainty), but may benefit if rates fall.
5-year fixes: you lock payment for longer (more stability), but may miss out if rates fall.

Rather than guessing rates, plan for resilience:

would you still be okay if your payment rose at the end of the fixed period?
do you have budget buffer for future changes?

Fees: upfront vs added to the mortgage

If you add a fee to the mortgage balance, you usually pay interest on it. That can be sensible if you want to keep cash, but it changes the real cost.

Practical comparison:

scenario 1: fee paid upfront
scenario 2: fee added to loan

Worked example: paying a fee upfront vs adding it to the mortgage

This is a simplified illustration to show the decision shape.

Assume:

Loan amount (without fee): £250,000
Term: 25 years
Rate: 5.00%
Product fee: £999

Option A: pay the fee upfront

Balance stays at £250,000.
You pay the fee as cash.

Option B: add the fee to the loan

Balance becomes £250,999.
Your monthly payment increases slightly.
You pay interest on the fee as part of the balance.

The difference is often not huge month-to-month, but over years it adds up. The decision is usually about priorities:

if preserving cash buffer matters, adding the fee can be rational
if minimising total cost matters and you have cash, paying upfront can be cheaper

Comparing 2-year fixes vs 5-year fixes (a practical planning lens)

Rather than trying to forecast rates, compare on resilience and friction:

Resilience (budget stability)

A 5-year fix can reduce payment uncertainty for longer. That can be valuable if your budget is tight or you want predictability.

Friction (how often you need to refinance)

Shorter fixes often mean you:

refinance more frequently
pay fees more frequently (depending on the deals you choose)
spend more time on admin and underwriting

If you expect to move or refinance quickly, a shorter fix may be fine. If you want stability and fewer “mortgage admin cycles”, longer fixes can appeal.

Remortgage friction: costs and time, not just money

Even when a remortgage is “free legals”, it still takes time and attention. If you are self-employed, have variable income, or have a complex case, the friction can be meaningful.

That’s why comparing deals should include the question:

“How often do I realistically want to go through switching?”

Sometimes a slightly more expensive deal that you keep longer is the better life decision, even if it is not the absolute cheapest on a spreadsheet.

A checklist for comparing two deals

Same loan amount and term in both comparisons
Compare the monthly payment
Compare total cost over 2/5 years
Include fees (and how they’re paid)
Check what happens after the fixed period
Stress-test with a higher rate
Confirm any early repayment charges (ERCs) if you might move/overpay

A step-by-step “calculator workflow” (so you can compare consistently)

If you want a repeatable workflow using Abodewise tools:

Decide the loan amount you’re comparing (or use the Mortgage calculator to get it from price + deposit).
For each deal, estimate the monthly payment using Mortgage repayment.
Pick your horizon (2 or 5 years).
Use Mortgage interest to estimate interest paid over that horizon for each rate/term assumption.
Add fees to the comparison:
- if the fee is upfront, add it directly
- if the fee is added to the loan, re-run with a slightly higher loan amount
Stress test the monthly payment by increasing the rate and asking whether your budget still works.

This gives you:

a monthly affordability view
a “total cost over horizon” view
a resilience view

None is perfect on its own, but together they make your decision less fragile.

Another worked example: break-even over 5 years

Assume:

Loan: £300,000
Term: 30 years
Horizon: 5 years

Deal A: lower rate, higher fee. Deal B: higher rate, lower fee.

If the lower-rate deal saves £40/month, that is £40 × 60 = £2,400 over five years. If its fee difference is £1,000, then over five years the lower-rate deal might win.

But if you only keep the mortgage for two years, the savings are £40 × 24 = £960, and the fee may dominate.

This is why the time horizon is the key to fee-vs-rate comparisons.

What to do next

Use Mortgage repayment to compare monthly payments.
Use Mortgage interest to compare interest over a 2/5-year horizon.
Use Mortgage for full scenario planning.

Summary

To compare mortgages well, you don’t need a perfect model. You need a consistent one:

compare monthly payments (budget safety)
compare total cost over a realistic horizon (2 or 5 years)
include fees and how they’re paid
consider ERCs and flexibility
stress test the payment with higher rates

If a deal looks good only in a best-case scenario, treat it as fragile. If it still looks comfortable under stress, it’s a stronger candidate.

When in doubt, prioritise a mortgage that keeps your monthly budget comfortable and your options open.

That approach usually reduces regret and surprises, especially when rates, fees, and life plans change unexpectedly.

It’s often the most human-friendly method.