The most common RSU mortgage mistakes (and how to avoid them)

RSUs (Restricted Stock Units) are now a common part of pay packages, particularly in tech, finance and professional services. They can make a meaningful difference to mortgage affordability—but only when they’re handled correctly.

When RSU income is treated as something it isn’t, or when key details are missed, applications can be delayed, declined, or reassessed after an offer is already in motion. This insight highlights the most frequent RSU-related mistakes seen in mortgage applications and what to watch for.

1) Declaring RSU income incorrectly

The biggest RSU mortgage mistake usually happens at the start: the way RSUs are entered or described doesn’t match how lenders assess them.

A common example is misclassifying RSUs as a “bonus”. On paper, RSUs can look similar to bonus income because they may vest into shares or cash-like value. However, lenders may treat RSUs differently from bonus payments.

Why this matters:

• Mortgage affordability calculations can change depending on how income is categorised (for example, salary vs bonus vs stock-based income).
• An Agreement in Principle (AIP) may be based on the figures entered, and may not reflect how the lender will later assess RSU income from the supporting evidence.

The result can be frustrating: an application appears to be progressing, then affordability is revisited once documents are reviewed.

2) Assuming every lender treats RSUs the same way

Another frequent issue is expecting one “RSU approach” to work across lenders.

In practice, lenders vary in how they assess stock-based income. For example, they may:

• take only part of the RSU value into account
• apply different assumptions depending on the scheme and vesting pattern
• focus on specific evidence (such as vesting history and current holdings)
• treat RSUs differently depending on whether they are ongoing, vested, or irregular

Because of these differences, the same set of RSU documents can lead to different outcomes depending on the lender.

3) Overlooking the impact of outgoings and deductions

Even when RSU income is presented correctly, affordability can still be overstated if outgoings aren’t captured properly.

Applicants sometimes focus on total income and forget that lenders assess affordability after considering committed costs. This can include items such as:

• pension salary sacrifice
• share scheme contributions
• student loan repayments
• car allowances (where applicable)
• other regular financial commitments

For remortgages in particular, this matters because affordability is reassessed based on your current circumstances, not just your previous borrowing.

4) Using the wrong documents—or not providing enough evidence

RSUs are document-led. If the information supplied doesn’t clearly show vesting patterns, current value, or how the income is generated, lenders may request additional clarification.

Common document-related pitfalls include:

• providing statements that don’t show vesting history clearly
• submitting incomplete evidence of ongoing RSU awards
• relying on estimates rather than scheme documentation

This can slow down processing and, in some cases, reduce the amount of RSU income that can be considered.

5) Treating an AIP as a guarantee

An AIP can be useful, but it should be treated as provisional—particularly where income is complex.

If RSUs are entered incorrectly, or if the lender’s method of assessing stock-based income differs from the way the application was prepared, the AIP may not reflect the final decision.

AIP accuracy can depend on:

• how the RSUs were described
• what evidence was available at the time
• the lender’s specific approach to stock-based income

6) Relying too heavily on rate comparison websites

Rate comparison sites can help you understand what’s available in the market. However, they’re not designed to reflect lender-specific treatment of RSU income.

Two people can see the same product headline rate but have different outcomes because affordability and eligibility depend on details that comparison tools can’t fully account for—especially where income is made up of salary plus equity.

7) Missing the “remortgage reality check”

For remortgages, RSU income can be reassessed as part of affordability checks. That means what worked before may not automatically work again if:

• your vesting pattern has changed
• your RSU awards are different from the previous period
• your outgoings have increased
• your overall income mix has shifted

A careful review of how RSU income is currently evidenced can reduce the risk of surprises later in the process.

What to do instead (practical steps)

RSU mortgages don’t have to be complicated, but they do require accuracy and consistency. The most effective approach is to:

• Present RSUs in a way that matches how lenders assess stock-based income (rather than assuming they’re treated like bonus income).
• Make sure the evidence aligns with the income being claimed, including vesting history and current scheme information.
• Account for deductions and outgoings so affordability reflects your true monthly position.
• Avoid treating an online estimate or AIP as final, particularly when RSUs are involved.

Why specialist handling can matter with RSUs

Because lenders can interpret RSU income differently, the way an application is prepared can influence how much equity income is considered.

Getting the basics right—how RSUs are described, what evidence is provided, and how affordability is calculated—can help reduce delays and prevent avoidable mistakes that derail applications.

Mortgage lending is subject to lender criteria and affordability assessments. RSU treatment varies by lender and individual circumstances.