Santander New Build Mortgages – The Complete Guide

Buying a new build is exciting — but it often comes with stricter rules than older homes. Most lenders want bigger deposits, shorter offer periods, and tighter affordability. Santander stand out because they’re still willing to offer 95% mortgages on new builds, making them one of the most accessible high street lenders for first-time buyers and movers alike.

At Strive, we specialise in new build mortgages. We work with Santander and every other major bank, so we can show you where Santander excel — and where an alternative lender might be a better fit.

What does Santander class as a new build?

Not every “modernised” home qualifies. Santander’s definition is clear: a property is a new build if it was constructed or converted in the last 24 months, has never been occupied, is sold by the developer, and has not been used for residential purposes before.

How much can I borrow with Santander?

When it comes to income multiples, Santander are competitive. They generally lend up to 4.5x income as standard, but in the right circumstances (strong affordability, higher income, or professional applicants) they can stretch to 5x, and in some cases up to 5.5x.

As with all lenders, they carry out a full affordability assessment. They’ll consider your debts, credit history, household bills, and spending patterns before confirming the maximum.

A unique advantage is that Santander recognise the lower running costs of new builds. Because these homes are more energy-efficient, they sometimes allow you to borrow more than if you were buying an older property.

What deposit do I need for a new build with Santander?

This is where Santander are almost unrivalled. Most lenders demand 15–25% deposits for new builds, especially for flats. Santander are one of the very few high street banks still comfortable with 5–10% deposits.

Here’s how their maximum loan-to-values (LTVs) work in practice:

Standard residential – up to 95% LTV (5% deposit)
Shared ownership – up to 90% LTV
Buy to Let – up to 75% LTV

New build houses

• Up to £570,000 → 95% LTV
• £570,001 – £1m → 90% LTV
• £1m – £2m → 85% LTV
• £2m – £3m → 75% LTV

New build flats

• Up to £380,000 → 95% LTV
• £380,001 – £1m → 90% LTV
• £1m – £2m → 85% LTV
• £2m – £3m → 75% LTV

👉 In short: Santander are one of the only mainstream lenders where a 5% deposit on a new build flat is even possible.

How long is a Santander mortgage offer valid for on a new build?

Build delays are common, and Santander take this into account.

• Their offers are valid for 9 months
• The completion deadline is also 9 months
• Extensions are available, but you’ll usually need to provide updated documents, undergo a new credit check, and sometimes arrange a fresh valuation

This is a longer validity than many lenders offer, but still needs managing carefully if your build is likely to slip.

Which warranties does Santander accept?

To protect buyers, Santander only lend on new builds with a recognised warranty or a Professional Consultant’s Certificate (PCC) for small developments.

Accepted schemes include NHBC, Premier Guarantee, LABC, Advantage, Build Zone, Checkmate, Protek, Global Home Warranties, One Guarantee, Ark Residential and others.

⚠️ Retrospective PCCs (arranged after completion) are not acceptable.

What about builder incentives?

Santander allow builder incentives, but they set clear limits depending on the deposit size.

• At or below 90% LTV – incentives can include stamp duty contributions, reasonable legal fees, fitted furniture, white goods, carpets, curtains, cashback up to 5% of purchase price, part exchange, removal fees and builder upgrade vouchers.
• Above 90% LTV – permitted incentives are narrower: fitted furniture, white goods, carpets, curtains, builder upgrade vouchers, legal fees, stamp duty contributions and estate agent fees.

They will not accept seller-funded deposits, mortgage subsidies, guaranteed rental income, or non-property-related gifts.

How do Santander compare to other lenders?

Santander are unrivalled when it comes to LTV and deposit flexibility. Being able to buy a new build flat or house with a 5% deposit is extremely rare in today’s market.

That said, they won’t always be the best fit. Other lenders may offer sharper rates or more generous affordability in certain cases. For example:

• Accord – flexible on affordability, often strong rates
• Halifax – popular with home movers, broad criteria
• Skipton – sometimes more generous with income multiples
• NatWest – strong on incentives (up to 15%) but higher deposit requirements

This is why we compare Santander against the wider market — to see whether the deposit flexibility outweighs affordability or rate advantages elsewhere.

Are Santander good for new build mortgages?

Santander are one of the strongest high street lenders in the new build space. They’re particularly good for:

• Buyers with small deposits (5–10%)
• First-time buyers purchasing flats
• Borrowers needing up to 5x–5.5x income in the right circumstances
• Clients needing longer offer validity (9 months)

They are less suitable if:

• You want to rely on incentives above 5%
• You need retrospective warranties
• You’re looking for the very lowest headline rates (in which case, an alternative lender may edge them)

Why choose Strive?

New build mortgages aren’t just “harder” — they’re more nuanced. Small details, like how incentives are treated or whether a warranty is acceptable, can derail an application if they’re not managed properly.

That’s where we come in. At Strive, we:

• Know Santander’s criteria inside out — we’ll flag potential issues early
• Work with every major lender — if Santander isn’t right, we’ll find who is
• Handle complex cases with developers daily — we know the pitfalls and how to avoid them
• Take care of timing — managing offer expiry dates and extensions so you’re never left exposed

We don’t just get you approved; we make the process straightforward, predictable, and stress-free.

📞 Thinking about Santander for your new build? Speak to us today — we’ll compare Santander against the whole market and secure the deal that’s right for you.

Santander New Build FAQs