What This Guide Covers
- The 24-month averaging calculation for annual and quarterly bonuses
- Why the month you apply matters as much as how much you earn
- Sign-on bonuses and one-time bonuses: why they almost never qualify
- Employer letter requirements and what the letter must confirm
How Underwriters Calculate Bonus Income
Bonus income is calculated by averaging the total bonus received over the most recent 24 months, documented using two years of W-2s. The bonus amount typically appears in Box 1 of the W-2 combined with base salary; the breakdown between base and bonus is confirmed using paystubs and the employer's pay history.
For annual bonuses paid at year-end, the two W-2s provide a complete two-year history. The total bonus over 24 months divided by 24 equals the monthly qualifying bonus income. If the bonus increased from year one to year two, the two-year average is used. If the bonus decreased, the most recent year's bonus is used rather than the average.
For quarterly bonuses, the analysis is the same: total bonus over two years divided by 24. The quarterly timing means there are eight bonus payments to review across the two W-2 years. Consistency matters; an underwriter who sees four strong quarters followed by four weak quarters will scrutinize the YTD paystub closely.
YTD paystub evidence of current-year bonus is required to confirm that bonus income is continuing at or above the prior year pace. An application submitted after the first bonus payment of the year, showing a YTD bonus consistent with prior years, is a stronger position than an application submitted before any current-year bonus has been received.
Required Documentation
- ✓Two years of W-2s (bonus amounts must be reconcilable with paystub history)
- ✓Most recent 30-day paystub showing YTD bonus received in the current year
- ✓Employer letter confirming bonus structure, historical amounts, and expectation that bonus will continue
- ✓Two years of federal tax returns if other income sources are present
- ✓For large bonuses: offer letter or bonus plan documentation confirming eligibility
What Most Lenders Get Wrong
- 1.Accepting a YTD paystub bonus figure without W-2 history. A borrower who received a large bonus in January of the current year has strong YTD figures but no historical pattern to confirm it is recurring. The W-2 history is required, not optional.
- 2.Not requiring an employer letter when bonus income is declining. The employer letter is the mechanism for explaining whether a decline is temporary (business conditions, leave of absence) or structural (plan change, lower tier). Without it, the underwriter must assume the decline is the new normal.
- 3.Counting a sign-on bonus as recurring income. A sign-on bonus is expressly one-time and non-recurring. Some borrowers who recently changed jobs have large sign-on bonuses on their current paystub. These cannot be averaged into qualifying income.
- 4.Failing to check whether the bonus was already counted through base salary grossing. Some employers blend base and bonus in Box 1 of the W-2 without a clear breakdown. Double-counting the bonus portion is a qualifying income inflation error.
The Month-of-Application Timing Problem
Annual bonus income creates a timing vulnerability that many borrowers do not anticipate. Most large bonuses are paid in the first quarter of the calendar year, January through March. If a borrower applies for a mortgage in October or November of a year when they expect a large bonus in February, that bonus has not yet been received and is not yet reflected in the current year's paystub.
In this situation, the underwriter can only use the two prior W-2 years for the bonus calculation. If the borrower had a strong bonus two years ago and a weaker bonus last year, the declining income rule applies and the calculation uses the lower year. The anticipated February bonus does not factor in.
The practical strategy: if you know a large bonus is coming in early next year, consider waiting until February or March to apply. At that point, your YTD paystub reflects the new bonus payment, which can be used alongside the two W-2 years to support the qualifying income figure.
Alternatively, some borrowers apply in the fall with a pre-approval that does not count the bonus, then update the application after the bonus is received if it is needed to close a specific transaction. This requires coordination with the timeline but can work if the closing date aligns with the bonus payment cycle.
Performance Bonuses vs Discretionary Bonuses: A Critical Distinction
Not all bonuses are the same from an underwriting standpoint. The nature of the bonus affects how confidently the underwriter can project its continuation.
Performance-based bonuses tied to measurable metrics, such as sales targets, production quotas, or department KPIs, have a clear structure that makes continuance easier to document. If the employer's letter confirms the bonus plan structure and the borrower's historic performance, the underwriter can point to an objective basis for expecting continued payments.
Discretionary bonuses are entirely at the employer's discretion with no guarantee of amount or payment. Some employers award them annually based on company profitability, which can vary significantly. An underwriter reviewing discretionary bonus income will be more conservative, and the employer letter must specifically state that the bonus is expected to continue based on current business conditions.
Profession-specific bonuses common in Kern County include performance pay for law enforcement officers, year-end bonuses for oil industry workers based on commodity pricing, and agricultural bonus structures tied to harvest yields. Each of these has a different pattern of variability, and the underwriter's view of continuance reflects that variability.
Bonus income timing catches more borrowers off guard than almost any other income issue I deal with. Someone who earns $80,000 in salary and a $40,000 annual bonus is a fundamentally different borrower in October versus March, purely because of where they are in the bonus cycle. I always ask about bonus timing upfront so we can either plan around it or document it correctly before the file goes to underwriting.
Do you have bonus income and want to know how much qualifies for your mortgage?
Call Dan at (661) 342-9381. He will review your specific situation and documentation in a free call.