The Shariah-compliant lender has raised its maximum age at the end of term from 85 to 99 years for UK residents.
Older clients, who would otherwise have no problem passing affordability tests, will now find it easier to get a loan, Gatehouse said.
Where there is a reliance on personal income, the maximum age remains 85.
Refinancing within six months of purchase for all buy-to-let customers will now be allowed, subject to an enhanced due diligence process.
The maximum finance-to-value for expats and international residents has been increased to 80 per cent from 75 per cent, while the minimum finance amount is reduced to £60,000.
And the minimum property value has been lowered from £100,000 to £75,000 for expats and international residents.
As part of further changes for expats, the bank will now require three months of bank statements from expats, rather than 12 months.
International residents will need to provide bank statements covering six months.
Charles Haresnape, chief executive of Gatehouse Bank (pictured), said: “We are always looking at ways to improve our buy-to-let and home purchase plan ranges to ensure we make the application process as easy as possible for our brokers and customers.
“We are able to make the latest changes to our criteria because of our human approach to underwriting, which means we take our customers’ full financial circumstances into account.”