Late fall is offer season for a lot of nurses. A new unit opens, a system across town dangles a sign-on bonus and a January start, and suddenly you're weighing a job change and a house at the same time. Both are good moves on their own. Stack them in the wrong order, though, and the income that makes you a strong buyer on paper can disappear from the lender's math right when you need it.

Before I sold houses I worked as a nurse, so I know what a nurse's paycheck looks like. It rarely looks like the flat salary a mortgage underwriter is built to read. Base pay is hourly, hours move around, and a real slice of the money comes from overtime, shift differentials, weekend premiums, and PRN shifts. Lenders can count most of that. They just have rules about how, and a job change can trip several of them at once.

How a lender sorts your paycheck

Most conventional loans follow Fannie Mae's Selling Guide, so its rules are a good stand-in for how your income gets read. Roughly, your pay lands in two buckets.

Base pay. If you're hourly and your hours vary, Fannie calls that variable base income, and it wants at least 12 months of history. The lender either averages your hours over the last year and multiplies by your current rate, or averages your actual earnings. Any raise has to be in effect before you close. A raise that starts in January doesn't help a December closing.

Overtime and bonuses. Here Fannie recommends a two-year history and allows as little as 12 months when other strengths in your file make up for it. The lender averages this year's and last year's earnings over at least 12 months. If your overtime has been dropping, the lender has to see that it has leveled off before counting it, and then it only counts the lower, steadier amount.

That last rule bites nurses more than you'd think. If you picked up every extra shift during a staffing crunch last year and cut back this year, the lender doesn't average the good year in. It looks at where you've settled.

Shift differentials, PRN, and sign-on bonuses

Shift differentials are where lenders differ the most. Fannie's guide doesn't name them. Some lenders treat a night or weekend differential as part of your base pay if it shows up on every paycheck because of the schedule you're assigned. Others treat it like overtime and average it. If differentials are a meaningful part of your income, ask the loan officer how they'll handle it before you apply, and ask your employer to spell it out on the verification of employment.

PRN and per diem work usually needs a track record before it counts, especially if it's a second job alongside a staff position. A few months of extra PRN shifts at another hospital may feel like real income, but to an underwriter it's too new to rely on yet.

Sign-on bonuses generally don't count as qualifying income, because they don't repeat. The cash can still help with your down payment or closing costs once it's actually in your account. Read the repayment clause, though. Most come with a commitment period, and a lender who sees that you owe the money back if you leave may want to know about it.

What a job change does to all of that

Changing employers doesn't automatically sink a mortgage. Staying in nursing with similar or better base pay is the kind of move lenders see every day, and many can work from your offer letter and first full paycheck. (If you'll close before your first day, see buying a home before your new job starts. Moving to contract work? Here's how lenders count 1099 income.) The trouble is usually with the variable pieces.

  • Your overtime history may not travel with you. Some lenders will let a long overtime history carry over if you're doing the same job and the new employer clearly offers overtime. Others won't count overtime until you've built some history at the new place.
  • Changing how you're paid can reset the clock. Moving from staff to PRN or travel, or from hourly to salaried, changes the type of income the lender is looking at, and the history for the new type starts over.
  • A lower base with a bigger differential can look worse on paper. If the new job's higher pay comes from differentials and incentives instead of base pay, your qualifying income may go down even though your take-home goes up.

Put a number on it. Say two years of overtime averages $900 a month. At a 43% debt-to-income limit, that overtime supports about $387 a month of house payment. At today's rates, that's roughly $55,000 of mortgage. If the new employer's overtime can't be counted yet, that's how much buying power walks out the door with your badge.

The order I'd do it in

  1. Talk to a lender before you accept the offer. Take your last two years of W-2s, your recent paystubs, and the offer letter. Ask the lender to run your qualifying income both ways: with the job you have and with the one you're considering.
  2. If you're already shopping, think hard before switching mid-deal. Lenders confirm your employment again shortly before closing. Resigning between contract and closing can stop a loan cold, even for a better-paying job.
  3. If you switch first, plan for a gap. Many lenders want at least one full paycheck from the new job, and your variable income may not count right away. Renting for a few months while it builds isn't a failure. I walked through that tradeoff in rent vs. buy for medical professionals.
  4. Don't count the sign-on bonus as income. Count it as cash for closing once it's in your account, and keep the repayment terms handy.
  5. Get the differential in writing. A line in the offer letter or the VOE stating the differential and the shifts it applies to gives an underwriter something solid to work with.

If a builder's year-end incentive is pulling you toward a December closing, all of this matters even more, since those offers ride on closing dates. I broke those deadlines down in what the builder-confidence slump means for a year-end deal. To see how a smaller qualifying income changes your price range, try my mortgage calculator.

And if you're still deciding where to live once the job is sorted out, start with where Houston nurses live and, if you're on nights, the neighborhoods that work for night-shift sleep. Call me before you sign either offer and we'll line up the timing so the job change and the house help each other.

Lenders apply these guidelines differently, and government-backed and physician or professional loan programs have their own rules. This article is general information, not lending advice. Confirm how your income will be counted with your loan officer before you change jobs or sign a contract.

Last updated October 2026