How UK Mortgages Work: Fixed, Tracker and Variable Explained

Mortgages are the biggest financial commitment most people ever make, and they come wrapped in enough jargon to make your eyes glaze over before you've finished the first paragraph. Fixed, variable, tracker, SVR, LTV, arrangement fees. It sounds like a different language, and it kind of is.

This article strips it back to the essentials. We'll cover how UK mortgages actually work, the three main types you'll see, and how to choose between them without needing a finance degree.

How a mortgage works, in 60 seconds

A mortgage is a loan secured against a property. You borrow money from a lender to buy a home, and you pay it back with interest over a long period, usually 25 to 35 years. The property itself acts as collateral: if you stop paying, the lender can repossess it.

Each month, your payment covers two things: part of the original loan (the capital) and the interest the lender charges for lending you the money. Over time, the balance shrinks and eventually you own the home outright.

The interest rate is the single biggest factor in how much your mortgage costs. A small difference in rate, even 0.5%, can mean tens of thousands of pounds over the life of the loan.

The three main mortgage types

1. Fixed-rate mortgage

Your interest rate is locked for a set period: typically two, three or five years. During that time, your monthly payment stays exactly the same, no matter what happens to the Bank of England base rate or the economy.

Pros:

  • Complete certainty on your monthly payment. Easy to budget.

  • Protection if interest rates rise.

  • Peace of mind, especially for first-time buyers.

Cons:

  • If interest rates fall, you're stuck paying the higher rate until the fix ends.

  • Early repayment charges (ERCs) usually apply if you want to leave the deal early. These can be 1% to 5% of the outstanding balance.

  • Fixed rates are sometimes slightly higher than the starting rate on a tracker or variable.

Fixed rates are the most popular choice in the UK. About 80% of new mortgages are fixed.

2. Tracker mortgage

Your interest rate "tracks" the Bank of England base rate, usually at a set margin above it. For example, base rate + 0.75%. If the base rate is 4.5%, your rate is 5.25%. If it drops to 4%, yours drops to 4.75%. If it rises, yours rises too.

Pros:

  • Transparent. You always know exactly why your rate is what it is.

  • You benefit immediately when rates fall.

  • Often has lower starting rates than fixed deals.

Cons:

  • Your monthly payment can go up if the base rate rises.

  • Budgeting is harder because payments can change.

  • Some trackers still have early repayment charges during an introductory period.

Trackers usually come in two forms: a deal period tracker (e.g., base rate + 0.75% for two years) and a lifetime tracker that lasts the full mortgage term with no early exit penalties.

3. Standard Variable Rate (SVR)

The SVR is the lender's default rate. It's the rate you move to automatically when your fixed or tracker deal ends, unless you remortgage to a new deal. The lender can change it whenever they want, by however much they want.

Pros:

  • No early repayment charges. You can leave or overpay freely.

  • No need to apply for anything. You're already on it.

Cons:

  • Almost always significantly more expensive than a fixed or tracker deal.

  • The rate is at the lender's discretion. It can go up even if the base rate doesn't.

  • Staying on SVR for more than a month or two is usually throwing money away.

Millions of UK homeowners sit on their lender's SVR without realising they're overpaying. If your deal has ended, remortgaging could save you hundreds a month.

Key terms you'll see everywhere

  • LTV (Loan to Value): how much you're borrowing as a percentage of the property's value. A £180,000 mortgage on a £200,000 house is 90% LTV. Lower LTV generally gets you a better rate because the lender's risk is lower.

  • Arrangement fee: a one-off fee the lender charges for setting up the mortgage. Often £500 to £1,500. Can sometimes be added to the loan, but then you pay interest on it.

  • Early Repayment Charge (ERC): a penalty for paying off or switching your mortgage during a fixed or tracker deal period. Usually 1% to 5% of the outstanding balance.

  • Term: how long you have to repay the mortgage. Longer terms mean lower monthly payments but more interest over the life of the loan.

  • Capital repayment vs interest-only: most residential mortgages are capital repayment, meaning you pay off the loan gradually. Interest-only means you only pay the interest each month and owe the full balance at the end. Interest-only is rare for residential buyers now.

How to choose between them

You want certainty and this is your first home

Go fixed. A two or five-year fix gives you a stable monthly payment while you're settling in and adjusting to homeowner costs. Most first-time buyers choose fixed for exactly this reason.

You think rates will fall

A tracker will pass the savings straight through to you. But if you're wrong and rates rise, so do your payments. Only choose a tracker if your budget can absorb a meaningful increase.

You want flexibility to overpay or move

Check the overpayment limits on any deal. Most fixed mortgages allow 10% overpayment per year without ERCs. If you need unlimited overpayment or plan to sell within two years, a tracker with no ERCs or staying on SVR briefly might make sense.

You're already on SVR

Remortgage as soon as possible. Talk to a mortgage broker (many are free, paid by the lender's commission) and switch to a new deal. You're almost certainly paying more than you need to.

Common doubts

  • "Should I fix for 2 years or 5?" Two-year fixes usually have slightly lower rates but you'll pay arrangement fees again sooner. Five-year fixes cost slightly more per month but give you longer stability. If you value certainty, five years is often the better call. If you think rates will drop, two years gives you an earlier chance to switch.

  • "Do I need a mortgage broker?" Not legally, but practically, yes. Brokers see the whole market (including deals not available direct) and save you hours of comparison. Many charge no fee to you because they're paid by the lender.

  • "What happens at the end of my deal?" You automatically roll onto SVR. Set a diary reminder 3 to 4 months before your deal ends and start shopping for a remortgage. Your new deal can be agreed and ready to start the day your old one expires.

  • "Can I be rejected for a mortgage?" Yes. Lenders assess your income, spending, debts and credit history. Getting an Agreement in Principle (AIP) early tells you roughly what you can borrow before you start house-hunting.

  • "What if I want to move during a fixed deal?" Most mortgage deals are "portable", meaning you can transfer them to a new property. But the lender will reassess your affordability for the new amount. If it doesn't work, you may face ERCs.

Where Mona fits

Mona helps with the money side of mortgage readiness: building your deposit, tracking your savings target, and keeping your spending healthy so your affordability looks solid when you apply. She also reminds you when your fixed deal is about to end so you don't accidentally drift onto SVR and start overpaying.

This article is for education only and is not financial advice. For free, impartial guidance on mortgages, MoneyHelper.org.uk (run by the UK government's Money and Pensions Service) has a mortgage calculator, comparison tools and step-by-step guides.

The bottom line

Fixed gives you certainty, tracker gives you transparency, and SVR is almost always worth leaving. Most UK buyers start with a fixed-rate deal for 2 or 5 years, then remortgage to a new deal when it ends. The worst thing you can do is let your deal expire and do nothing.

Mortgages sound complicated, but the core decision is actually simple: how much risk are you comfortable taking with your biggest monthly outgoing?

Pick the type that lets you sleep at night. Then set a reminder to review it before the deal ends.

If you're on SVR right now, speak to a fee-free mortgage broker this week. If you're buying for the first time, get an Agreement in Principle before you book a viewing. Both take under an hour and could save you thousands.

Join Mona’s early access waitlist

Join the waitlist

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How UK Mortgages Work: Fixed, Tracker and Variable Explained

Mortgages are the biggest financial commitment most people ever make, and they come wrapped in enough jargon to make your eyes glaze over before you've finished the first paragraph. Fixed, variable, tracker, SVR, LTV, arrangement fees. It sounds like a different language, and it kind of is.

This article strips it back to the essentials. We'll cover how UK mortgages actually work, the three main types you'll see, and how to choose between them without needing a finance degree.

How a mortgage works, in 60 seconds

A mortgage is a loan secured against a property. You borrow money from a lender to buy a home, and you pay it back with interest over a long period, usually 25 to 35 years. The property itself acts as collateral: if you stop paying, the lender can repossess it.

Each month, your payment covers two things: part of the original loan (the capital) and the interest the lender charges for lending you the money. Over time, the balance shrinks and eventually you own the home outright.

The interest rate is the single biggest factor in how much your mortgage costs. A small difference in rate, even 0.5%, can mean tens of thousands of pounds over the life of the loan.

The three main mortgage types

1. Fixed-rate mortgage

Your interest rate is locked for a set period: typically two, three or five years. During that time, your monthly payment stays exactly the same, no matter what happens to the Bank of England base rate or the economy.

Pros:

  • Complete certainty on your monthly payment. Easy to budget.

  • Protection if interest rates rise.

  • Peace of mind, especially for first-time buyers.

Cons:

  • If interest rates fall, you're stuck paying the higher rate until the fix ends.

  • Early repayment charges (ERCs) usually apply if you want to leave the deal early. These can be 1% to 5% of the outstanding balance.

  • Fixed rates are sometimes slightly higher than the starting rate on a tracker or variable.

Fixed rates are the most popular choice in the UK. About 80% of new mortgages are fixed.

2. Tracker mortgage

Your interest rate "tracks" the Bank of England base rate, usually at a set margin above it. For example, base rate + 0.75%. If the base rate is 4.5%, your rate is 5.25%. If it drops to 4%, yours drops to 4.75%. If it rises, yours rises too.

Pros:

  • Transparent. You always know exactly why your rate is what it is.

  • You benefit immediately when rates fall.

  • Often has lower starting rates than fixed deals.

Cons:

  • Your monthly payment can go up if the base rate rises.

  • Budgeting is harder because payments can change.

  • Some trackers still have early repayment charges during an introductory period.

Trackers usually come in two forms: a deal period tracker (e.g., base rate + 0.75% for two years) and a lifetime tracker that lasts the full mortgage term with no early exit penalties.

3. Standard Variable Rate (SVR)

The SVR is the lender's default rate. It's the rate you move to automatically when your fixed or tracker deal ends, unless you remortgage to a new deal. The lender can change it whenever they want, by however much they want.

Pros:

  • No early repayment charges. You can leave or overpay freely.

  • No need to apply for anything. You're already on it.

Cons:

  • Almost always significantly more expensive than a fixed or tracker deal.

  • The rate is at the lender's discretion. It can go up even if the base rate doesn't.

  • Staying on SVR for more than a month or two is usually throwing money away.

Millions of UK homeowners sit on their lender's SVR without realising they're overpaying. If your deal has ended, remortgaging could save you hundreds a month.

Key terms you'll see everywhere

  • LTV (Loan to Value): how much you're borrowing as a percentage of the property's value. A £180,000 mortgage on a £200,000 house is 90% LTV. Lower LTV generally gets you a better rate because the lender's risk is lower.

  • Arrangement fee: a one-off fee the lender charges for setting up the mortgage. Often £500 to £1,500. Can sometimes be added to the loan, but then you pay interest on it.

  • Early Repayment Charge (ERC): a penalty for paying off or switching your mortgage during a fixed or tracker deal period. Usually 1% to 5% of the outstanding balance.

  • Term: how long you have to repay the mortgage. Longer terms mean lower monthly payments but more interest over the life of the loan.

  • Capital repayment vs interest-only: most residential mortgages are capital repayment, meaning you pay off the loan gradually. Interest-only means you only pay the interest each month and owe the full balance at the end. Interest-only is rare for residential buyers now.

How to choose between them

You want certainty and this is your first home

Go fixed. A two or five-year fix gives you a stable monthly payment while you're settling in and adjusting to homeowner costs. Most first-time buyers choose fixed for exactly this reason.

You think rates will fall

A tracker will pass the savings straight through to you. But if you're wrong and rates rise, so do your payments. Only choose a tracker if your budget can absorb a meaningful increase.

You want flexibility to overpay or move

Check the overpayment limits on any deal. Most fixed mortgages allow 10% overpayment per year without ERCs. If you need unlimited overpayment or plan to sell within two years, a tracker with no ERCs or staying on SVR briefly might make sense.

You're already on SVR

Remortgage as soon as possible. Talk to a mortgage broker (many are free, paid by the lender's commission) and switch to a new deal. You're almost certainly paying more than you need to.

Common doubts

  • "Should I fix for 2 years or 5?" Two-year fixes usually have slightly lower rates but you'll pay arrangement fees again sooner. Five-year fixes cost slightly more per month but give you longer stability. If you value certainty, five years is often the better call. If you think rates will drop, two years gives you an earlier chance to switch.

  • "Do I need a mortgage broker?" Not legally, but practically, yes. Brokers see the whole market (including deals not available direct) and save you hours of comparison. Many charge no fee to you because they're paid by the lender.

  • "What happens at the end of my deal?" You automatically roll onto SVR. Set a diary reminder 3 to 4 months before your deal ends and start shopping for a remortgage. Your new deal can be agreed and ready to start the day your old one expires.

  • "Can I be rejected for a mortgage?" Yes. Lenders assess your income, spending, debts and credit history. Getting an Agreement in Principle (AIP) early tells you roughly what you can borrow before you start house-hunting.

  • "What if I want to move during a fixed deal?" Most mortgage deals are "portable", meaning you can transfer them to a new property. But the lender will reassess your affordability for the new amount. If it doesn't work, you may face ERCs.

Where Mona fits

Mona helps with the money side of mortgage readiness: building your deposit, tracking your savings target, and keeping your spending healthy so your affordability looks solid when you apply. She also reminds you when your fixed deal is about to end so you don't accidentally drift onto SVR and start overpaying.

This article is for education only and is not financial advice. For free, impartial guidance on mortgages, MoneyHelper.org.uk (run by the UK government's Money and Pensions Service) has a mortgage calculator, comparison tools and step-by-step guides.

The bottom line

Fixed gives you certainty, tracker gives you transparency, and SVR is almost always worth leaving. Most UK buyers start with a fixed-rate deal for 2 or 5 years, then remortgage to a new deal when it ends. The worst thing you can do is let your deal expire and do nothing.

Mortgages sound complicated, but the core decision is actually simple: how much risk are you comfortable taking with your biggest monthly outgoing?

Pick the type that lets you sleep at night. Then set a reminder to review it before the deal ends.

If you're on SVR right now, speak to a fee-free mortgage broker this week. If you're buying for the first time, get an Agreement in Principle before you book a viewing. Both take under an hour and could save you thousands.

Join Mona’s early access waitlist

Join the waitlist

All articles