Fannie Mae Guidelines: Fixed-Rate Loan Requirements

What Makes a Loan Fixed-Rate Under Fannie Mae Guidelines

A fixed-rate loan means your interest rate stays the same for the entire loan term. Whether you get a 15-year or 30-year mortgage, that rate never changes. This differs from adjustable-rate mortgages where the rate can fluctuate over time.

Your monthly payment structure must follow specific rules. You pay the same principal and interest amount every month, due on the first day of each month. The payment covers interest for the previous month plus a portion of the principal balance.

Say you close on January 15th with your first payment due March 1st. That March payment covers interest from January 15th through February 28th, plus principal reduction. This "payment in arrears" structure is standard for all Fannie Mae fixed-rate loans.

Full Amortization Requirements

Fannie Mae only purchases fully amortizing fixed-rate loans. This means your monthly payments gradually pay down the entire loan balance over the loan term. No balloon payment comes due at the end.

Each payment includes both principal and interest. Early in the loan term, most of your payment goes toward interest. As years pass, more goes toward principal reduction. By your final payment, you own the home free and clear.

Interest-only loans or loans with balloon payments do not qualify for Fannie Mae purchase. The lender needs assurance that borrowers will steadily build equity through regular principal payments.

Non-Assumable Loan Feature

All Fannie Mae fixed-rate loans are non-assumable. This means when you sell your home, the buyer cannot take over your existing mortgage. They must qualify for their own financing.

This protects Fannie Mae from credit risk. When the original borrower sells, Fannie Mae gets paid in full from the sale proceeds or the buyer's new loan. The buyer's creditworthiness becomes irrelevant to the existing loan.

Your lender must mark the loan as non-assumable in their delivery system to Fannie Mae. This designation is automatic for all conventional fixed-rate loans originated after the note date.

Temporary Interest Rate Buydowns

Fixed-rate loans can include temporary interest rate buydowns for primary residences and second homes. These arrangements reduce your interest rate for the first few years of the loan.

A common structure is a 2-1 buydown. Your rate starts 2% below the note rate in year one, then 1% below in year two, then jumps to the full note rate in year three. Someone pays the difference upfront at closing.

The seller, builder, or even you can fund the buydown. The money goes into an escrow account that supplements your monthly payments during the reduced-rate period. Investment properties cannot use temporary buydowns under Fannie Mae guidelines.

Required Documentation for Fixed-Rate Loans

Your lender needs standard mortgage documentation to sell your fixed-rate loan to Fannie Mae. This includes the promissory note, deed of trust or mortgage, and any applicable riders.

The note must clearly state the fixed interest rate and payment terms. It should specify level monthly payments and the full amortization schedule. Any temporary buydown arrangements require additional documentation showing the funding source and payment structure.

For buydown loans, expect to provide the buydown agreement and evidence that funds are properly escrowed. The lender must verify that buydown payments will cover the interest rate differential for the specified period.

Why Fannie Mae Prefers Fixed-Rate Loans

Fixed-rate loans offer predictable cash flows for Fannie Mae's mortgage-backed securities. Investors know exactly what interest payments to expect over the loan's life, making these securities easier to price and sell.

The non-assumable feature protects against credit deterioration. Fannie Mae underwrote the original borrower, not future buyers. When properties sell, Fannie Mae gets repaid rather than inheriting unknown credit risks.

Full amortization ensures steady principal reduction. This builds borrower equity over time and reduces Fannie Mae's loss exposure if foreclosure becomes necessary. Borrowers with equity have stronger incentives to maintain their properties and make payments.

Common Issues with Fixed-Rate Loan Structure

Payment timing problems can disqualify loans from Fannie Mae purchase. If your loan requires payments on dates other than the first of the month, or if payments don't cover interest in arrears, the loan won't meet guidelines.

Some lenders mistakenly structure loans with interest paid in advance rather than arrears. This creates complications for Fannie Mae's servicing systems and securities cash flows. The payment structure must match Fannie Mae's requirements exactly.

Buydown documentation often causes delays. If the buydown agreement is unclear about funding sources or payment calculations, underwriters may reject the loan. Make sure all buydown paperwork is complete and accurate before closing.

Investment property buydowns are prohibited but sometimes slip through initial underwriting. If your loan officer suggests a buydown for a rental property, remind them that Fannie Mae guidelines only allow this for primary residences and second homes.

References

For the official guidelines, see B2-1.4-01: Fixed-Rate Loans in the Fannie Mae Selling Guide.