The mutual will now also consider 100% of allowances and overtime for affordability calculations.
The scope of the professionals range is now open to all nationalities. This includes foreign nationals with a visa working in professions such as paramedics, nurses, teachers and lecturers, members of the armed forces, firefighters and police.
Acceptable visa types include Skilled Worker visas, Health and Care Worker visas, Spouse visas, British National Overseas visas and Ancestry visas.
The society will accept 100% of allowances and overtime for these roles subject to a six-month track record.
The range is available up to 95% loan to value (LTV) with no minimum income criteria, no minimum time in the UK and no credit scoring.

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The society has also enhanced its criteria on expat applications and it will no longer be a requirement that applicants have a minimum of 12 months in their current role.
Christopher Blewitt (pictured), head of mortgage distribution at Darlington Building Society, said: “We’re seeing strong demand from key workers and other professionals with complex income arrangements, including those who are foreign nationals. These criteria changes are a direct response to that demand. Whether it’s shift-based roles, variable allowances or overtime, we understand how important it is to consider 100% of income, not just basic salary, when making lending decisions.”
Earlier this month, the society released five-year fixed rate deals up to 95% LTV under the Own New Rate Reducer partnership.