The comparison

A home and an investment are two different transactions.

People use the word mortgage for both, which hides how little they have in common. Different lenders, different assessment, different deposit, different tax, different law, and a completely different definition of what a good outcome looks like. Here is the whole comparison in one place.

Residential vs investment, in full
 Residential, you live in itInvestment, you let it out
What the lender assessesYour income, your commitments, your credit fileThe rent the property will produce, stress-tested
Typical maximum loanAround 4.5x income, sometimes 5x or moreWhatever the rent supports, capped by loan to value
Minimum deposit5%25%, occasionally 20%
Rate levelLowerHigher, with larger product fees
Repayment methodCapital and interest, almost alwaysUsually interest only
Stamp dutyStandard rates, first-time buyer relief may applyStandard rates plus a 5% surcharge on the whole price
Income tax on rentNot applicableYes, at your marginal rate
Mortgage interest reliefNot applicableA 20% tax credit only, if held personally
Capital gains tax on saleNormally exempt as your main residencePayable on the gain
FCA regulatedYesUsually not
Ownership structurePersonal namePersonal name or a limited company
Ongoing obligationsInsurance and maintenanceLicensing, gas and electrical safety, EPC minimum, deposit protection, agent fees, voids
Main riskRates rise, or your income stopsVoids, arrears, rate rises and rules changing
What success looks likeSomewhere to live, and the debt shrinkingNet yield after every cost, plus capital growth

The mental shift

When you buy a home, the mortgage is a cost you are trying to minimise while you enjoy living somewhere. When you buy an investment, the mortgage is a tool and the property is a small business - one with customers, regulations, maintenance and a tax return.

The most common mistake we see is somebody applying home logic to an investment: choosing the property they would like to live in, in the area they would like to live in, and being surprised that the yield is poor. The second most common is the reverse - treating a home purely as an asset and stretching into a house that makes every month miserable.

What the numbers actually look like

Take the same £250,000 property two ways. These are illustrations to show the shape of the difference, not quotations.

As a home, 10% deposit

Deposit £25,000
Loan £225,000 over 30 years
Stamp duty £2,500, or £0 as a first-time buyer
Repayment capital and interest, so the balance falls every month
On sale normally no capital gains tax

As a let, 25% deposit

Deposit £62,500
Loan £187,500, usually interest only
Stamp duty £2,500 plus a £12,500 surcharge
Rent needed roughly £1,246 a month to pass a 145% stress test at 5.5%
On sale capital gains tax on the gain

The investment needs £47,500 more cash on day one before a single thing has gone wrong. That is the number people underestimate, and it is why the honest first question is not what the yield is but whether the deposit and the surcharge leave you with a reserve for a boiler and three months of voids.

Which should you do?

  • Buy a home first if you are renting, have a deposit around 5% to 15%, and want the lowest cost of borrowing available to you. It also protects first-time buyer stamp duty relief, which you only get once.
  • Buy an investment if you already own where you live, have 25% plus the surcharge plus a genuine cash reserve, and are prepared to run it as a business for at least five years.
  • Consider let to buy if you are moving and your current home would rent well - you keep the asset and release equity for the next deposit. Two mortgages, more risk, and the surcharge applies, though it is reclaimable if you sell the old home within three years.
  • Look at a limited company if you are a higher-rate taxpayer buying to let and reinvesting the profit rather than spending it. Talk to an accountant as well as to us.

One thing you cannot do

You cannot buy on a residential mortgage and quietly let the property out. It breaches the mortgage terms and can make the entire loan immediately repayable, as well as invalidating your insurance. If your plans change after you buy, ask the lender for consent to let - it is usually granted, often for a small fee, and it takes one phone call. What is not survivable is being found out.

Common questions

Residential and investment questions

Can I use equity in my home as the deposit for a rental?

Yes, and it is the most common way people fund a first buy to let. You remortgage your home for a higher amount and take the difference as cash. You need the affordability on your own income to support the larger residential loan, and you should be clear that you have moved risk onto the roof over your head. It is a sound strategy done deliberately and a bad one done casually.

Do I lose first-time buyer status if I buy an investment first?

Yes. First-time buyer stamp duty relief requires that you have never owned any residential property anywhere in the world, and that includes one you never lived in. On a £300,000 first home that relief is worth £2,500, and more above that. It is a real cost of investing before you buy a home, and it should be in the calculation.

Is the 5% surcharge ever refundable?

Yes, in one specific situation: you bought a new main residence before selling your old one, so you briefly owned two. Sell the previous main residence within three years and you can reclaim the surcharge from HMRC. It does not apply to a straightforward buy-to-let purchase where you keep both properties.

Which gives a better return?

Nobody can tell you that honestly, and be careful of anyone who does. What we can do is show you the real cash in, the real cash out and the sensitivity to a rate rise or a three-month void for a specific property, so you are comparing something concrete rather than a story about the property market.

Start here

Not sure which one your situation calls for?

Tell us what you own, what you earn and what you are trying to achieve. We will lay out both routes with the real numbers and say which one we would do.


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  • No credit check, no hard search
  • A reply within one working day

Prefer to talk now? Call 0333 339 7301 or email [email protected].

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