Lease Commencement Date ASC 842: Practitioner Guide

Lease Commencement Date ASC 842: Practitioner Guide

Getting the lease commencement date wrong under ASC 842 is not a rounding error. It misstates your ROU asset, your lease liability, your discount rate, and every disclosure that flows from those figures. The SEC has flagged commencement date determinations in comment letters, and auditors treat it as a high-judgment area. This guide gives finance teams a concrete, step-by-step workflow for identifying the right date, handling the five most common edge cases, and documenting the conclusion so it survives scrutiny.

Key takeaway: Under ASC 842-10-20, the lease commencement date is "the date on which a lessor makes an underlying asset available for use by a lessee." That single sentence governs every measurement and classification decision in lessee accounting. It is almost never the lease signing date, and it is not the rent start date.

What Is the Lease Commencement Date Under ASC 842?

The commencement date is the date the lessor makes the underlying asset available for the lessee's use -- not the date the contract is signed, not the date rent begins, and not the date the lessee moves in. ASC 842-10-20 has defined it this way since ASU 2016-02, and the definition has not changed through ASU 2021-05 or ASU 2023-01.

Three dates that preparers routinely confuse:

As Grant Thornton's ASC 842 guide states directly: "Under ASC 842, an entity assesses lease classification on the commencement date of the lease." PwC's Leases guide reproduces the same definition verbatim. The codified language is unambiguous. The judgment lies in applying it.

What Happens on the Commencement Date?

At commencement, four things happen simultaneously -- and all four are anchored to that single date:

1. Lease classification. All five criteria under ASC 842-10-25-2 are evaluated as of commencement: transfer of ownership, purchase option reasonably certain to exercise, lease term relative to economic life (the 75% guideline), present value of payments relative to fair value (the 90% guideline), and specialized nature with no alternative use. Classification uses the asset's fair value and remaining economic life as of commencement, not as of signing.

2. ROU asset and lease liability recognition. Under ASC 842-20-30, the lessee recognizes both the ROU asset and the lease liability on the commencement date. The lease liability equals the present value of unpaid lease payments over the lease term, discounted at the commencement-date rate.

3. Discount rate lock-in. The rate -- either the rate implicit in the lease or the lessee's incremental borrowing rate (IBR) -- is determined as of commencement and locked in unless a remeasurement event occurs later. More on the IBR timing trap below.

4. Initial direct cost and incentive accounting. Per ASC 842-20-30-5, the ROU asset at commencement equals: initial lease liability + initial direct costs + prepaid lease payments made before or at commencement, minus lease incentives received before or at commencement.

For lessors, commencement is equally consequential: sales-type and direct financing lessors derecognize the underlying asset and recognize a lease receivable; operating lessors begin recognizing lease income. See ASC 842-30.

How to Identify the Commencement Date: A Step-by-Step Workflow

The controlling question is always: on what date did the lessor make the asset available for the lessee's use? Work through these steps in order.

Step 1: Read the lease for physical possession language

Look for clauses that specify when the lessee receives keys, access, or physical possession. The contractual "commencement date" written in the lease is a starting point, not the answer. If the contract grants early access -- even for fit-out or construction -- that access date may be the true commencement date for accounting purposes.

Step 2: Apply the "available for use" test

Ask: does the lessee have the right to control the use of the asset during this period? Deloitte's DART Chapter 5.1 is explicit: if the lessee obtains the right to use the asset before the contractual lease term begins -- for example, to install equipment or perform renovations -- the commencement date is the earlier date when the lessee controls the asset, provided the lessor has made it available. Control, not cash flow, is the trigger.

Step 3: Work through the five common edge cases

See the section below. Each scenario has a different answer, and getting the wrong one creates a systematic error in your lease population.

Step 4: Lock in the IBR as of that date

Once the commencement date is confirmed, determine the IBR as of that specific date. If commencement is materially later than signing -- common in build-to-suit leases with 12-18 month construction periods -- the rate at signing is irrelevant. Per Grant Thornton's guide, the IBR must reflect the rate the lessee would pay to borrow on a collateralized basis over a similar term in a similar economic environment as of commencement.

Step 5: Classify pre-commencement costs

Costs incurred before commencement fall into three buckets:

• Capitalize as initial direct costs: incremental costs of obtaining the lease directly attributable to it, such as external legal fees tied specifically to the lease negotiation.
• Add to ROU asset as prepaid rent: lease payments made before commencement.
• Expense as incurred: internal costs, allocated overhead, general legal fees, and any cost that would have been incurred regardless of whether the lease was obtained.

Step 6: Document and support the determination

ASC 842 does not define "available for use" beyond the master glossary. That creates a judgment area, and auditors know it. Your documentation should capture: the physical possession date, any early access clause language, the basis for concluding whether the lessee controlled the asset during early access, and the commencement date conclusion. A one-page memo with the lease clause excerpts attached is the minimum standard for audit support.

Five Edge Cases and the Right Answer for Each

1. Early access for tenant improvements

A lessee receives keys on January 1 to begin fit-out. The contractual lease start is March 1, and rent starts April 1. What is the commencement date?

Answer: January 1, if the lessee controls the use of the asset during the fit-out period. The key question is who owns the improvements being constructed. If the lessee is building its own leasehold improvements, it controls the space and commencement has occurred. If the lessor owns the improvements and the lessee is acting only as the lessor's construction agent, the asset is not yet available for the lessee's use and commencement has not occurred. Deloitte's DART illustrates exactly this distinction in its Examples 5-1 and 5-2.

The practical consequence: the lease term for accounting purposes runs from January 1, not March 1, and the ROU asset and lease liability are recognized on January 1. The four rent-free months are inside the lease term and affect the straight-line lease cost calculation.

2. Build-to-suit leases

A company signs a lease for a warehouse that will be constructed over 18 months. The lease is signed in January 2025 and the building is expected to be ready in July 2026.

Answer: July 2026 (or whenever the asset is substantially complete and available for the lessee's use). The commencement date is not the signing date, and it is not the date construction begins. Per Deloitte DART, for build-to-suit leases the commencement date is the date the underlying asset is substantially complete.

This creates two important follow-on questions. First, if construction is delayed -- say, commencement slips from July 2026 to October 2026 -- does that constitute a lease modification? Generally no: EY's Financial Reporting Developments guide confirms that changes to the estimated commencement date that are not modifications do not trigger remeasurement. The entity simply updates its estimate of when commencement will occur. Second, the IBR must be determined as of the actual commencement date, not the signing date. With a gap of 12-18 months, the rate difference can be material.

3. Master lease agreements with multiple assets

A company signs a single master lease for 50 fleet vehicles, with vehicles delivered in batches over six months.

Answer: each vehicle has its own commencement date -- the date that specific vehicle is made available for use. Per Grant Thornton's guide, a single master lease can generate multiple commencement dates, each triggering a separate ROU asset and lease liability recognition event. This is a common source of systematic error in lease accounting systems that default to the contract execution date for the entire portfolio.

4. Sale-leaseback transactions

A company sells a building and simultaneously leases it back.

Answer: the closing date of the sale transaction. The commencement date of the leaseback is the date the sale is recognized and the leaseback begins. The seller-lessee recognizes the ROU asset and lease liability as of that date under ASC 842-40. The leaseback is a new lease with its own classification test, discount rate, and initial measurement -- all anchored to the closing date.

5. Leases with delayed commencement under common control (ASU 2023-01)

For private companies implementing ASU 2023-01 (effective for public entities for fiscal years beginning after December 15, 2023, and for all other entities after December 15, 2024), leasehold improvements on common-control leases are now amortized over the useful life of the improvement rather than the lease term. The commencement date still triggers initial recognition, but the amortization period for leasehold improvements capitalized at commencement may now extend beyond the lease term. Private companies implementing this update in 2025-2026 need to revisit their commencement date determinations for any common-control lease where leasehold improvements were previously amortized over a shorter lease term.

The IBR Timing Trap

This is the gap that most freely available articles miss entirely. When a significant period separates lease signing from commencement -- as is routine for build-to-suit arrangements -- the IBR at signing and the IBR at commencement can differ materially.

As KPMG's Leases Handbook notes, for leases with a 12-18 month gap between signing and commencement, the IBR at commencement can differ materially from the rate at signing, particularly in volatile rate environments. The rate used to measure the lease liability must reflect the rate the lessee would pay to borrow on a collateralized basis as of the commencement date -- not as of signing.

For finance teams with build-to-suit pipelines or long pre-delivery periods, the practical implication is clear: do not lock in an IBR at signing and carry it forward to commencement. Reassess the rate when the commencement date is confirmed, and document the basis for the commencement-date IBR separately from any rate estimated at inception.

For context on how rate environment shifts affect ASC 842 and other disclosure obligations, see our piece on what rate changes mean for SEC disclosures.

What Goes Wrong When the Date Is Wrong

A wrong commencement date is not an isolated error. It cascades:

• ROU asset and lease liability: both are misstated if measured at the wrong date, because the discount rate, the lease payments included, and the lease term all change.
• Lease classification: the five criteria are evaluated as of commencement using the asset's fair value and economic life as of that date. A wrong date means a potentially wrong classification.
• Disclosure errors: ASC 842-20-50 requires disclosure of weighted-average remaining lease term and weighted-average discount rate. Both are derived from commencement date measurements. A systematic error in commencement dates produces a systematic error in both disclosures.
• Maturity analysis: the undiscounted lease payment maturity table is keyed to the lease term, which starts at commencement. Wrong date, wrong table.
• Restatement risk: if the error is material, correction requires restating the balance sheet, income statement, and disclosures for every period affected.

The SEC has cited lease accounting as a recurring comment letter focus since ASC 842 adoption, with staff questions covering completeness of lease populations, appropriateness of discount rates, and identification of commencement dates for complex arrangements.

The ERP and Lease System Problem

Many ERP systems and older lease accounting platforms default to the contract execution date when a user enters a new lease. That default is wrong under ASC 842 for any lease where the asset is not immediately available on signing day. For companies with large lease portfolios -- retail chains, equipment-heavy manufacturers, logistics operators -- this default creates a systematic population-level error.

When evaluating or configuring lease accounting software, verify that the system supports a separate "available for use" date field distinct from the contract date, and that initial recognition, classification testing, and IBR determination all key off that field. For a broader evaluation framework, see our 2026 guide to AI lease accounting software.

Lessor Accounting at Commencement

Most articles focus exclusively on the lessee. For companies that are both lessees and lessors -- real estate companies, equipment manufacturers, banks with leasing subsidiaries -- the commencement date triggers distinct lessor accounting under ASC 842-30:

• Sales-type leases: the lessor derecognizes the underlying asset, recognizes a net investment in the lease (the lease receivable plus any unguaranteed residual asset), and recognizes selling profit or loss at commencement.
• Direct financing leases: similar to sales-type, but selling profit is deferred and recognized over the lease term.
• Operating leases: the lessor keeps the asset on its balance sheet and begins recognizing lease income, typically on a straight-line basis, from the commencement date.

Commencement Date Documentation Checklist

For each lease, the audit file should include:

• Copy of the lease agreement with the physical possession or early access clause highlighted
• Written conclusion on the commencement date with the "available for use" analysis
• If early access is present: analysis of who owns the improvements and whether the lessee controls the asset during the access period
• For build-to-suit: evidence of substantial completion (certificate of occupancy, landlord delivery notice, or equivalent)
• For master leases: individual commencement date log for each asset in the portfolio
• IBR support memo dated as of the commencement date (not the signing date)
• Pre-commencement cost analysis: initial direct costs vs. prepaid rent vs. period costs
• ROU asset calculation per ASC 842-20-30-5: lease liability + initial direct costs + prepaid payments, minus incentives received

FAQ

What is the lease commencement date under ASC 842? It is the date the lessor makes the underlying asset available for use by the lessee, per the ASC 842-10-20 Master Glossary. It is the date lease accounting begins: the lessee recognizes the ROU asset and lease liability, classifies the lease, and locks in the discount rate.

Is the commencement date the same as the lease signing date? No. The signing date (sometimes called the inception date) is when the parties execute the agreement. The commencement date is when the asset is physically available for the lessee's use. These can be days, months, or in build-to-suit cases, years apart.

What is the difference between lease commencement and rent commencement? The rent commencement date is when rent payments begin under the lease. The ASC 842 commencement date is when the asset is available for use. ASC 842-10-55-20 states explicitly that "the timing of when lease payments begin under the contract does not affect the commencement date of the lease." The months between commencement and rent start are inside the lease term and carry lease cost.

When did ASC 842 lease accounting start? ASC 842 (introduced by ASU 2016-02) became effective for public business entities for fiscal years beginning after December 15, 2018 (calendar year 2019). For private companies and not-for-profits, the effective date was fiscal years beginning after December 15, 2021 (calendar year 2022), following FASB deferrals.

Does early access for tenant improvements trigger commencement? It depends on control. If the lessee is constructing its own leasehold improvements and controls the space during the access period, commencement has occurred. If the lessee is acting only as the lessor's construction agent and the lessor owns the improvements, the asset is not yet available for the lessee's use and commencement has not occurred.

What happens if a build-to-suit lease is delayed? A delay in the expected commencement date -- for example, a construction overrun -- does not automatically constitute a lease modification requiring reassessment of all terms. The entity updates its estimate of when commencement will occur. However, the IBR must be determined as of the actual commencement date, not the originally expected date.