First-Time Home Buyer's Guide to Mortgages

Buying a home for the first time is mostly administrative, and almost none of it is intuitive the first time. The good news is that the hard parts — the deposit maths, the affordability limits, the order of the process — are all knowable in advance. This guide covers what to do, in the order you should do it.

What actually narrows your options

Three things determine what you can buy, in this order of importance:

1. Your income, against your debts. This sets the size of the loan a lender will approve, and it is arithmetic rather than judgement — see how DTI works.
2. Your deposit. The size of your deposit directly limits the price, because the loan is the price minus the deposit.
3. Your credit file. A moderate effect on the rate you are offered, and a large effect on which products you qualify for at all.

Work out the first two before you look at any property, and everything after that becomes a search rather than a negotiation. People who browse first spend months emotionally attached to homes they cannot buy.

The deposit, and getting help with it

Deposits are typically 5% to 20%, and the difference changes what you can buy, what you pay, and what you are exposed to.

• 5–10% accessible to more first-time buyers, but you will pay mortgage insurance, usually for the life of the loan.
• 15% usually removes the mortgage insurance requirement.
• 20% generally unlocks the best rates and the widest choice.

Government-backed schemes to assist with deposits exist in most jurisdictions and are well worth exploring. In the US, federal resources such as the U.S. Department of Housing and Urban Development (HUD.gov) loan directory detail FHA, VA, and USDA financing options, while Freddie Mac down payment assistance programs help qualify buyers with down payments as low as 3%. In addition, the Consumer Financial Protection Bureau (CFPB) Owning a Home toolkit provides step-by-step guidance on navigating closing costs and lender requirements.

A gift from family is the most common route, and the rules vary. Some schemes explicitly prohibit it, and most require the money to be genuinely yours rather than repaid later — so document the gift and do not quietly plan to repay it.

What a purchase really costs up front

This is where first-time buyers are most often caught. On a 300,000 home, the cash you need is not 5%.

So a 5% deposit is really 7–15% of the purchase price. If you can only just raise the deposit, you probably cannot raise the rest, and that is when offers fall through after months of work.

Which produces the single most common first-time buyer failure: not affording the property, but affording it and then being unable to complete. The deposit is a hurdle, but it is not the biggest one. Budget the full figure in the table above, and keep the difference between that and your deposit as a genuinely separate pot you do not plan to spend on the house.

A useful test: if your total cash requirement is more than about 40% of everything you have saved, you are probably buying a property that needs a bigger deposit or a cheaper price. That is a better outcome discovered now than a failed sale discovered in month four.

The process, in order

1. Get a mortgage in principle. A broker’s estimate of what you could borrow, often valid for 90 days. It costs nothing and it sizes your search honestly.
2. Fix your budget and your walk-away number. Decide both before you view, because both will be tested.
3. View and offer. Research the local market first — sold prices, time on market, and whether the area is a chain.
4. Offer accepted, then full application. The lender verifies your income and debts here, and where problems surface. Have documents ready.
5. Survey and valuation. The lender values the property for the lender. A bad survey can collapse the price or make the buyer repair.
6. Conveyancing, exchange and completion. Weeks, not days. Book nothing non-refundable until completion.

One crucial piece of timing advice: exchange and completion are different dates. Between them you may need to have moved out but not yet moved in, with a mortgage running and no property. Budget for that, and check whether your mortgage offers a payment holiday for it.

The approval checklist

Most rejections happen for reasons that were visible weeks earlier. These are the ones worth checking before you spend any time searching.

1. Run your own affordability first. Before you fall in love with a property, know the number. Our home affordability calculator will give you a maximum and a recommended price, and the gap between them is your real margin.
2. Check your credit file yourself, before a lender does. Errors are common and fixing one that is not yours takes weeks.
3. Clear what you can, and stop taking on new credit. Every monthly payment you clear raises the loan you qualify for — our guide to the debt-to-income ratio has the arithmetic.
4. Have your income documented in advance. Payslips, tax returns and bank statements, for every source you intend to declare.
5. Check for anything that will change between offer and completion. A new job, a bonus you have not received, a deposit that depends on a sale that has not completed. Each of these is a common reason a sale collapses late.
6. Get more than one mortgage offer. Rates vary between lenders for the same borrower, and a modest improvement applied to a twenty-year loan is a large sum of money. See our guide to refinancing for why comparing monthly payments instead of totals goes badly.

None of this is difficult. It is simply easier to do in sequence rather than in a panic two days before completion, which is when most of it actually happens.

Getting approved without surprises

Have ready, because lenders ask and delays cost weeks:

• Three months of payslips, or two years of tax returns if self-employed
• Three months of statements for every current account
• Existing mortgage or tenancy details, including your landlord’s address
• Identification and proof of address
• Details of every debt, including cards with small balances
• Your deposit funds, evidenced — a bank statement is usually enough

Two things cause most application failures. The first is undisclosed debt, discovered during a credit check and treated as a question of honesty rather than luck. The second is a change of circumstances between offer and application, including new credit accounts.

If your deposit comes from a gift, a property sale or an unpaid bonus, tell your broker at the start. Most problems are solved in advance.

What a bigger deposit actually buys

Almost every first-time buyer treats a larger deposit as a way to get a cheaper mortgage. It is not. This surprises people, so here it is with numbers.

On a 4,800,000 income with no other debts, at 7.5% over 20 years, here is what each deposit actually produces:

Four million more of deposit, and the monthly payment moves by 60. The housing budget is capped by your income, not by your cash, so extra deposit does not buy a cheaper house — it buys a more expensive one at the same monthly cost.

That changes what a bigger deposit is actually for. Its real benefits are elsewhere, and they are still worth having:

• It removes PMI. At 20% you stop paying mortgage insurance entirely, which is a genuine and permanent saving that never appears in the payment figure.
• It usually improves the rate. Lenders price a lower loan-to-value more favourably.
• It gives you equity from day one, which matters if prices fall or if you need to sell sooner than planned.
• It strengthens any offer you make. Sellers prefer a buyer who does not need a mortgage condition to complete.

So aim for 20% if you can reach it without emptying your emergency fund, and treat the money as buying lower friction rather than a smaller payment. If you can only manage 5%, that is a completely reasonable place to start — you are paying for the privilege of not waiting, and the premium is a known and finite one.

Is it better to keep renting?

This question arrives for almost everyone and it is more tractable than it feels, because you are comparing two known monthly figures plus an assumption about future house prices.

The honest comparison is not rent against mortgage, because they are not the same thing. It is rent plus the value of what a deposit would otherwise have earned, against mortgage plus the equity you are building. A mortgage payment of 2,500 with a 20% deposit builds equity that a rent of 1,500 does not, and that equity is a real asset even while you are paying more.

In addition, if you buy and then sell within a few years you pay the round-trip costs of stamp duty or transfer tax, legal fees, surveys and an estate agent’s commission, typically five to eight per cent of the price. Renting is genuinely cheaper if you are certain to move. The uncertainty is the whole argument: renting is cheaper if you move, buying is usually cheaper if you stay.

So the question is not really “rent or buy”, it is “how long might I be here”. If the honest answer is two years, renting is almost certainly the better financial decision and the mathematics is not close. If it is ten, the round-trip costs are spread so thinly that they stop being the deciding factor, and the equity you build starts to dominate.

There is also the cash-flow version of the same question, and it is the one that actually decides it for most people. A mortgage payment of 2,500 with a 20% deposit is not comparable to a rent of 1,500 — but it is comparable to a rent of 1,500 plus 1,000 a month invested. The difference between the two is the real monthly cost of owning, and once you have calculated it honestly, the decision usually makes itself.

That is the comparison to run before you decide, rather than rent against payment. Our home affordability calculator will give you the realistic total housing cost including tax and insurance, which is the number this comparison needs.

So the useful exercise is to calculate the break-even tenure. How many years must you expect to stay before buying costs less than renting? If that number is longer than your realistic expectation, rent. If it is shorter, buy. It takes ten minutes and it converts the most emotional decision in personal finance into an arithmetic one.

Mistakes that are expensive and easy to avoid

1. Waiting until you are ready to buy. The improvement that takes six months is paying down revolving balances and correcting any credit file error, then getting a fresh in-principle decision.
2. Not budgeting for tax and insurance. A payment of 2,528 is closer to 3,300 once property tax, insurance and any mortgage insurance are added.
3. Skipping the survey to save money. It is the only independent assessment of the building you are about to own. Skip it and you inherit the problem.
4. Buying at the top of your limit. The maximum a lender approves is a stress test, not a budget. See how much house you can afford.
5. Committing before the survey result. Do not exchange on a property with an unreported structural issue, and do not exchange unconditionally without that protection.
6. Assuming the mortgage is approved. An agreement in principle is not an offer. The formal application can still be declined.

The mortgage calculator sizes the loan and the payment for your deposit, rate and term, and shows the full month-by-month schedule. Pair it with the affordability calculator, which checks what your income and debts genuinely support, and you will know your limit before you start looking rather than after an offer falls through.