The change to crioteria is effective from Monday 14 July, in line with the rest of the RBS and NatWest mortgage channels.
The lender said: “As a responsible lender, NatWest places a strong focus on affordability and measures to safeguard its customers. This change of policy is being introduced to create greater consistency between buy-to-let and residential lending policy.”
The maximum LTV for buy-to-let mortgages remains at 75% as does the maximum loan size of £500,000.
All other remaining criteria remains unchanged. The new policy will also be introduced on the same date to buy-to-let mortgages from RBS Intermediary Partners and RBS and NatWest mortgages available through the retail channels.