Many UK expats earn in a foreign currency, whether that’s USD, EUR, AED, or something more niche. But when it comes to applying for a UK mortgage, that income isn’t treated the same as a UK salary. In 2025, lenders are tightening how they assess affordability for non-GBP income — applying stress rates, exchange rate margins, and higher documentation standards.

In this blog, we break down the key challenges expats face with income verification, how currency risk impacts mortgage decisions, and how Willow Private Finance helps structure successful applications despite these complexities.

Why Foreign Currency Income Is Treated Differently

Lenders see foreign income as inherently riskier — not because it’s less stable, but because of the currency conversion risk it introduces.

Key concerns include:

• Exchange rate volatility: Income may be worth less in GBP at the time of repayment.
• Liquidity of currency: Not all currencies are easy to convert or hedge.
• Income stability: Offshore earnings may be more variable or dependent on employment terms that UK lenders don’t recognise.

In response, many lenders now apply a deduction of 10% to 25% to foreign income before assessing affordability — even if your actual earnings are consistent.

📖 Read more in How Foreign Currency Income & Liquidity-Based Lending Are Reshaping UK Mortgage Approvals

Currency Risk and the Impact on Loan Size

In 2025, lenders are stress-testing applications more aggressively to protect against currency movements. Here’s how that plays out in real terms:

• An expat earning $200,000 USD may only be assessed as earning £120,000–£130,000 GBP.
• Borrowing capacity is reduced as a result — meaning larger deposits are often required to achieve the same purchase price.
• This adds to the trend we explored in Why Expat Mortgages Require Large Deposits and How to Prepare

If you’re earning in a more volatile currency (such as ZAR, INR, or TRY), lenders may apply harsher haircuts or decline the application altogether unless additional assets are presented.

Documentation Requirements for Foreign Income

Lenders will require more than a payslip. In 2025, the typical documentation for expat income includes:

• Employment contract or offer letter
• Payslips (usually 3–6 months)
• Tax returns or year-end income summary
• Bank statements showing receipt of income
• Translation or authentication (if documents are not in English)

Some lenders are now requesting documents in both native currency and GBP equivalent, and expect applicants to explain fluctuations or bonuses in writing.

If you’re self-employed, the process becomes even more complex. Read Mortgages for Self-Employed Borrowers in 2025 for insight into how Willow helps package these cases.

The Role of Private Banks and Specialist Lenders

Not all lenders treat foreign income equally. While mainstream high-street banks may reject or heavily discount it, specialist lenders and private banks often take a more nuanced view.

In many cases, these lenders will:

• Assess income in the original currency
• Look at asset backing and total net worth
• Take a portfolio view of affordability (especially for HNW clients)

We discuss this in greater detail in Private Client Finance in 2025: Tailored Lending for Complex Profiles and Private Bank Mortgages Explained

Case Example: Structuring Around Currency Volatility

A client earning in EUR through a multi-jurisdictional business was initially declined by their high-street bank. Willow arranged a mortgage through a specialist lender that:

• Used a 90-day average exchange rate to calculate affordability
• Accepted foreign language payslips with certified translation
• Considered the client's liquid assets as secondary support

The final offer allowed for 70% LTV on a £1.1M London flat — demonstrating that foreign income, when properly presented, needn’t be a barrier.

📖 Related reading: Can You Buy Property in the UK Without a Visa or Credit History?

How Willow Private Finance Can Help

We work daily with clients earning in:

• USD, EUR, AED, HKD, SGD
• Income from offshore companies
• Dividends, bonuses, and variable contracts
• Mixed income from employment and investments

We know how to present these profiles to lenders, calculate GBP-adjusted affordability, and source mortgage terms from providers who understand international income streams. Whether you’re applying from abroad or recently returned to the UK, we’ll ensure your application reflects the full strength of your financial position.

📖 If you’re returning to the UK, also see: Property Finance for Returning UK Expats in 2025

📞 Want Help Navigating Today’s Market?

Book a free strategy call with one of our mortgage specialists.

We’ll help you find the smartest way forward, whatever rates do next.