NatWest changes new home deposit requirements and Interest Only mortgage rules

by Aaron Strutt

Nov 07 2025

NatWest lowers the deposit requirement for newly built flats and houses

NatWest has lowered the deposit requirement for borrowers buying New Build properties, reducing the upfront deposit needed and opening the doors for more buyers:

• New Build Houses: Applicants will now need a 5% deposit with NatWest rather than a 10% deposit.

• New Build Flats: Applicants will now need a 10% deposit with NatWest rather than a 15% deposit. 

These improved lending levels make it easier for customers to get the keys to a brand-new home while keeping their savings requirements more manageable.

Why Choose a New Build?

Beyond the reduced deposit options, New Build properties are often popular because of the lower monthly running costs, access to green mortgage products and potential peace of mind from modern construction standards and new-build warranties.

NatWest also enhances Interest-Only mortgage options

For customers exploring Interest Only mortgages, NatWest has also expanded its loan-to-value limits across several repayment strategies—providing greater flexibility and more opportunities to tailor mortgage arrangements to individual circumstances.

What’s Changing?

• Sale of Main Residence (Interest Only):
  Loan-to-value increased from 50% to 75%

• Other Investments as Repayment Strategy (Interest Only):
  Loan-to-value increased from 75% to 80%

• Part & Part Mortgages (all repayment strategies):
  Loan-to-value increased from 75% to 85%
  (75% Interest Only / 10% Capital & Interest)

Part & Part mortgages offer a blend of repayment and interest-only—ideal for borrowers seeking a balance between flexibility and affordability. 

Aaron Strutt, product director at Trinity Fiancial, says: "NatWest has tweaked its new build property and interest only mortgage criteria to make it easier for borrowers to either buy a home or reduce their monthly repayments. Many lenders are currently making changes to their rates and acceptance rules. NatWest consistently offer some of the most competitively priced rates in the mortgage market."

Get expert mortgage advice from Trinity Financial

At Trinity Financial, our team of experienced London mortgage brokers specialises in helping borrowers secure the right deal. We work with all major lenders and can guide you through the full application process.

Call Trinity Financial on 020 7016 0790 to secure a new build property mortgage or an Interest Only mortgage or book a consultation

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