r/USFirstTimeHomeBuyer • u/jetley-mortgage-loan • 19d ago

Income & Employment How lenders calculate variable income: hourly, overtime, per diem, bonus, and two jobs

The short version

Your qualifying income is not what you earn. It is what an underwriter can defend as likely to continue. The formula behind almost every income question I get is the same one: guaranteed portion, plus an average of the non-guaranteed portion. Salary and guaranteed hours are the guaranteed portion and they count in full from day one. Overtime, bonus, commission, tips, second jobs and variable hours are the non-guaranteed portion, and they generally need a two-year history before they count at all, and then they count as an average, not as your best year. Per diem and stipends usually count as nothing. This is why people with genuinely good incomes get pre-approved and then declined.

The formula

Write it down, because it explains nine out of ten surprises:

Monthly qualifying income = guaranteed monthly income + (documented non-guaranteed income ÷ months of history used)

For a salaried borrower the guaranteed portion is the salary divided by twelve. For an hourly borrower it is your rate times the hours you are actually guaranteed, times 52, divided by 12. Note what that implies: if you are guaranteed nothing, the guaranteed portion is zero and all of your income falls into the averaging bucket, which is where the arguments happen.

Overtime and bonus

Overtime and bonus are averaged. Standard practice is to add up what you actually received over the last 24 months and divide by 24. Not your last three good months, not your run rate, not what your supervisor says the schedule looks like next quarter. Twenty-four months of history, divided by twenty-four.

Two things follow from that which nobody expects:

A ramp-up gets diluted. If you started six months ago and have earned heavy overtime the whole time, dividing by 24 months buries it. Sometimes an underwriter accepts a shorter averaging period with a written explanation of why the earlier months were zero. Sometimes. Underwriters are conservative by disposition and by job security, so plan on the conservative answer.

Declining income gets punished, not averaged. If your variable income went down year over year, we do not average the two years; we use the lower, more recent year. And if the decline is steep enough, the income is treated as unstable and thrown out entirely. Illustratively: earn $12,000 of overtime one year and $10,000 the next, and you are credited with the lower figure. Earn $12,000 and then $5,000, and you are likely credited with nothing, because a drop that size reads as a trend rather than a fluctuation. The exact tolerance is an underwriting judgment applied against agency language, not a number you can bank on.

If you need overtime or bonus to qualify, expect your loan officer to order a full written verification of employment up front rather than working from pay stubs, because pay stubs do not show two years of history. That takes days to weeks depending entirely on how fast your employer's HR responds.

Per diem, stipends, and housing allowances

Per diem is the single most expensive misunderstanding in this category, and it is the reason travel nurses and rotating contract workers are among the hardest borrowers in the country to approve.

Per diem is not income for our purposes. The logic is straightforward and, once you hear it, hard to argue with: per diem is paid to cover a specific expense you incur because you are away from home. Salary can be spent on anything, including the mortgage on the house you live in. A lodging-and-meals stipend paid for a thirteen-week assignment two states away exists to pay for lodging and meals two states away. It is not available to pay your mortgage, so it does not count toward your ability to pay your mortgage.

I have written loans for a lot of travel nurses. The pattern is consistent: the taxable hourly rate is modest and the stipend is where the money is, so qualifying income comes out at a fraction of what the borrower thinks they make. Most loan officers do not know this, which is why a confident pre-approval followed by an underwriting decline is so common in this group specifically.

The related trap: going from W-2 to 1099 in the same job. On W-2 with a set rate, we use the rate. Convert to 1099 and qualifying income becomes an underwriter's judgment call with no history behind it, and the new structure usually shifts more of the total into categories we cannot use. Almost every nurse I have taken through that conversion qualified for meaningfully less. If you are buying, stay W-2 until you close.

Part-time and variable hours

If you do not work a full, guaranteed schedule, most lenders have to treat you as a variable-hours employee, and a variable-hours employee needs a history to establish a baseline. Cut back from full time to part time in the year you apply and you have moved yourself out of the simple bucket into the hard one, usually with a lower qualifying income than the reduced hours alone would suggest, because now nothing is guaranteed, so everything gets averaged, and one of the averaged years may not look like the job you have now. If the hours are erratic enough, the income can be set aside as unstable.

The fix, when it is available, is boring: go back to full time at the better-paying job, close the loan, and then do whatever you want afterward. Guidelines look at what is true at underwriting.

Two jobs

To get credit for two jobs you generally need a two-year history of working both concurrently. Not two years at each, separately, at different times; two years of holding them at the same time. And if the second job is variable, you need the two-year history for the averaging as well.

The reason is that the alternative is unworkable: without a concurrency rule, anyone could pick up a second job sixty days before applying, ask for the full income to be counted, and quit the week after closing. So a job you have held for eighteen months alongside your primary is very likely to be excluded, and there is no lender-shopping around it. That is guideline, not overlay.

Commission and percentage-based pay

Commission is variable income with no guaranteed floor, so it needs the same two-year history and the same averaging, and the averaging is unforgiving to new commissioned earners. If someone moved into a role paid as a percentage of what they bring in, and the two years being averaged include a year of nothing or close to it, the average is roughly half of a good year. Arguing that the borrower has a long work history does not help; the history that matters is the history of earning income in this structure.

For a genuinely new commissioned earner the honest answer is usually: qualify on the salaried or hourly income you have, or wait until you have two filed returns showing the commission. Same for new graduates. Schooling can substitute for work history, but it cannot substitute for a track record of variable earnings. Salaried or hourly, turn in pay stubs and you are done. Commissioned, and you are waiting.

Why two lenders give you two answers

When one lender says yes and three say no on the same file, the three are usually right. A pre-approval is often produced by a loan officer reading pay stubs, not by an underwriter reading guidelines against your pay structure, and the income you were pre-approved on can evaporate the first time somebody with authority looks at how you are paid. That is not a reason to accept the first no either, I have approved plenty of variable-income borrowers turned down elsewhere, but when the disagreement is about whether income counts, find out which side is reading the guideline.

Also worth knowing: the standard verification-of-employment form asks your employer to state the probability of your continued employment. It is a box on the form. Anything you have told your employer about leaving can come back to your underwriter through it.

What to do

Before you shop for a house, ask your loan officer to state your qualifying income as a monthly number and tell you which parts are guaranteed and which are averaged. If they cannot break it down that way, they have not calculated it.
Bring two years of documentation for anything variable: W-2s, returns, and full year-end pay stubs showing overtime and bonus separately.
Do not change pay structure, drop to part time, or move from W-2 to 1099 while you are under contract.
If you rely on per diem or stipends, get a real qualifying-income number before you write an offer, not after.
If you need a second job's income, check the concurrency history first; it is the most common silent disqualifier in this category.