An assumption budget must reconcile transferred reserve ownership and the actual closing balance, not just subtract the seller’s mortgage from the price. Here, reserve reimbursement and replenishment turn a seemingly funded purchase into a $120,000 cash deficit.
Hypothetical acquisition settlement case. A buyer agrees to pay $7 million for a property with a $4.2 million existing mortgage. It is attracted to the 4.25% coupon and assumes the acquisition needs $2.92 million: price plus $120,000 of transaction costs, less the debt being assumed. It has $3.1 million of total project cash and believes the deal is funded.
The loan can be assumed only if the actual approving parties consent and all required documents are completed. Fannie Mae’s fixed-rate product summary is one primary example of assumption being subject to new-borrower review; it does not establish the terms of this fictional mortgage. The case holds approval otherwise satisfied so it can isolate a settlement cash error.
Find the reserve ownership before calculating the closing wire
Assume the existing lender holds $200,000 of funded reserves. Under the invented purchase agreement, that balance remains with the loan and is transferred for the buyer’s benefit, but the buyer must reimburse the seller dollar for dollar. The lender also requires an additional $100,000 deposit at assumption. The post-closing restricted reserve will be $300,000.
These arrangements are negotiated assumptions, not universal servicing rules. The actual purchase agreement, loan documents, reserve statements and assumption consent determine who owns the funds and whether they transfer, return to the seller or must be replaced.
| Assumption settlement component | Treatment | Amount |
|---|---|---|
| Purchase price | Amount paid or satisfied for property | $7,000,000 |
| Transaction/assumption costs | Includes all assumed fees in this case | $120,000 |
| Seller reimbursement for transferred reserve | Additional settlement use | $200,000 |
| Buyer reserve top-up | New restricted deposit | $100,000 |
| Total economic uses | $7,420,000 | |
| Existing debt assumed | Liability taken over, not new cash wired to buyer | ($4,200,000) |
| Total required buyer equity | $3,220,000 | |
| Earnest money already paid | Portion of that same equity | ($300,000) |
| Remaining buyer closing wire | $2,920,000 |
The original $2.92 million estimate happens to equal the correct remaining wire. That numerical coincidence can hide the mistake. The buyer has already spent $300,000 of its $3.1 million, leaving only $2.8 million available to wire. The closing shortage is $120,000.
Earnest money is credited once, as previously contributed equity. It is not an extra source in addition to the full $3.1 million. The $200,000 existing reserve is also not free seller equity: under the stated purchase terms, the buyer pays for it and cannot simultaneously treat it as unrestricted acquisition cash.
Compare a new loan on the same reserve basis
Assume an alternative new mortgage funds $5 million at 7%, with $220,000 of all-in transaction costs and a newly funded $300,000 restricted reserve. The old reserve returns to the seller under this alternative, and there is no separate reserve reimbursement by the buyer. The purchase price remains $7 million.
Total new-loan uses are $7.52 million. After $5 million of debt, buyer equity is $2.52 million, including the $300,000 earnest money; the remaining wire is $2.22 million. Against $3.1 million of project cash, the buyer retains $580,000 outside the funded uses, subject to any other real obligations.
Assumption requires $700,000 more equity: it provides $800,000 less debt but saves $100,000 of transaction costs. Both routes end with the same $300,000 restricted reserve. Comparing the assumption without its reserve purchase against a fully reserved new loan would distort the cash difference.
If the seller agrees to waive the $200,000 reserve reimbursement, the assumption equity falls to $3.02 million and fits the buyer’s budget with $80,000 remaining. That is a negotiated economic concession. It cannot be presumed from the lender’s statement that the reserve account transfers.
Quantify the payment benefit without calling it a return
Assume the existing $4.2 million balance amortizes over 240 remaining monthly payments at a nominal 4.25% rate, with maturity in 36 months. Its level monthly payment is approximately $26,007.85, or $312,094 annually. The balance after 36 payments is approximately $3,773,350, due at that maturity in this model.
Assume the $5 million new loan amortizes over 300 monthly payments at 7%, with a seven-year term. Its monthly payment is approximately $35,338.96, or $424,068 annually. The assumption saves about $111,973 in annual scheduled payments, but uses more opening equity and matures four years earlier.
These payments use a monthly rate equal to nominal annual rate divided by twelve, without contract-specific rounding or day-count adjustments. The payment difference includes different amortization and principal amounts. Dividing it by the additional $700,000 equity would not produce a valid investment yield or a complete economic comparison.
Close only against a dated, complete reconciliation
Obtain the actual balance effective at the proposed assumption date, next scheduled payment, accrued amounts, current reserve statements, fee invoice and seller credits. A stale balance estimate can change both the price equity and the payment allocation at settlement. The lender or servicer must confirm the operative schedule.
The decision has three separate tests: approval of the actual buyer, enough cash for settlement including reserve ownership, and a funded plan for the remaining maturity. This case fails the second test by $120,000 until additional capital or changed purchase terms are documented. The lower coupon is valuable only after those conditions produce an acquisition that can actually close.
Sources and evidence
- Fannie Mae — Fixed-Rate Mortgage Loans Term SheetAssumption · Checked 2026-10-21 · Current product summary checked October 21, 2026. Approval depends on the actual transaction; the case is a fictional generic loan, not a Fannie offer.
Source dates and applicability matter. Report an error or a changed source.