Treasury Regulations
The operational rulebook and the constructive-receipt regulation.
2.1 · Reg. §15a.453-1 — Installment Method Regulations
Implements the installment method: defines selling price, contract price, gross profit, and gross profit percentage; governs contingent payment sales (§15a.453-1(c)) — providing ratable basis recovery when the FMV of contingent payments cannot be reasonably ascertained; and addresses installment obligations and related-party rules.
This is the operational rulebook for computing each year's recognized gain in an SIS. The contingent-payment rules matter when the sale price is not fully fixed (e.g., an earn-out), though most SIS structures use fixed, scheduled payments precisely to keep the calculation clean and the obligation determinable.
2.2 · Reg. §1.451-2 — Constructive Receipt of Income
Income is "constructively received" in the year it is credited to the taxpayer's account, set apart, or otherwise made available so the taxpayer may draw on it — unless the taxpayer's control of receipt is "subject to substantial limitations or restrictions." Income is not constructively received if it is not yet available without such a substantial restriction.
This is the governing regulation for the third pillar. The entire SIS deferral collapses if the seller is treated as having constructively received the sale proceeds in the year of closing. The structure is engineered around §1.451-2: the seller must have no right to demand, accelerate, or assign the funds; the proceeds must not sit in an account the seller can reach; and the funding annuity must be owned by the assignment company, not the seller. The "substantial limitations or restrictions" language is the doctrinal hook — the seller's payment rights are intentionally made nontransferable and irrevocable so that the future payments are not "made available" in year one.
2.3 · T.D. 8675 — Preamble Confirming the §453B Standard
In adopting regulations on debt-instrument modifications, Treasury expressly stated that the §1001 "significant modification" standard does not govern whether an installment obligation has been disposed of for §453B purposes. Instead, the pre-existing §453B cases and rulings continue to control.
This is the regulatory confirmation that the lenient §453B "material change in the seller's rights" test — not the stricter §1001 modification rules — applies to obligor substitutions. It directly supports the SIS conclusion that swapping the buyer for an assignment company is not a taxable disposition.
2.4 · Temp. Reg. §1.163-9T — Personal Interest
Treats certain interest, including the §453A interest charge for individuals, as nondeductible personal interest.
Explains why the §453A interest charge stings individual SIS sellers more than corporate ones — the charge cannot be deducted. A planning input, not a structural bar.
2.5 · REG-109348-22 — Proposed Regulations on Monetized Installment Sales
Proposes to identify monetized installment sale (MIS) transactions — and substantially similar transactions — as listed transactions under §6011, triggering disclosure obligations (Form 8886) and material-advisor requirements (§6111/§6112). The regulation lists seven hallmarks, the core of which is a seller who receives a loan equal to the sale proceeds in year one while reporting installment deferral — i.e., monetizing the note without economic deferral.
This regulation targets the abusive monetized structure, not the SIS. The defining MIS feature — a back-to-back loan that puts cash in the seller's hands while claiming deferral — is exactly what a legitimate SIS does not do (the SIS seller takes no loan and genuinely defers receipt). Practitioners (and ACTEC's comment letter) have warned the proposal is drafted broadly enough to risk sweeping in legitimate three-party SIS transactions, which is why the eventual final regulation's scope matters to the industry. Status as of June 2026: still proposed, not finalized — the comment period closed in 2023, the hearing was cancelled, and the project has slipped on recent IRS Priority Guidance Plans.