Salary, hourly & variable base income
A steady hourly rate does not automatically mean the monthly income is fixed. The hours matter.
Fannie fixed base income
Fannie distinguishes fixed base income from variable base income. Fixed base can be salary or an hourly rate with guaranteed minimum hours. Minor pay-period variation in hours does not automatically make the income variable.
Fannie variable base income
Variable base includes a fixed hourly rate with fluctuating hours or an hourly rate that itself changes. Fannie generally requires averaging using at least 12 months of income. If earnings are decreasing, the lender must determine whether the current level has stabilized.
Shorter work history
Fannie asks lenders to evaluate the most recent two-year work history, but a shorter history can be acceptable when positive factors reasonably support stability. That is different from a blanket rule that every borrower must be in the same job for two years.
Official guide baseline
Fannie Mae Selling Guide · Freddie Mac Seller/Servicer Guide
Agency guide and AUS findings control over summaries. Lender overlays may be more restrictive.