The Threshold Question: Is It a Separate Contract?

A lease modification is any change to the terms and conditions of a lease that was not part of the original contract — extending or shortening the term, adding or removing an underlying asset, or changing the consideration. The very first question ASC 842 asks is whether the modification should be accounted for as a separate contract or as a change to the existing one.

A modification is accounted for as a separate contract only when both of the following are true:

• The modification grants the lessee an additional right of use not included in the original lease (for example, additional floor space or additional equipment units), and
• The increase in consideration for that additional right of use is commensurate with its standalone price, adjusted for the circumstances of the contract

If both conditions hold, the lessee accounts for the new right of use exactly as it would a brand-new lease, and the original lease is left untouched. This is the easy case. Most modifications in practice fail at least one of these conditions and fall into the second category: not a separate contract.

Modifications That Are Not Separate Contracts

When a modification is not accounted for as a separate contract, the lessee first reassesses the lease classification as of the modification’s effective date, then applies one of two remeasurement approaches depending on whether the modification decreases or otherwise changes the scope of the lease.

Decrease in Scope (Partial Termination)

If the modification decreases the scope of the lease — for example, the lessee gives back part of a leased floor, or shortens the term — the lessee must:

1. Decrease the carrying amount of the ROU asset to reflect the partial or full termination, with any difference between the reduction in the lease liability and the proportionate reduction in the ROU asset recognized as a gain or loss
2. Remeasure the remaining lease liability using a revised discount rate

Any Other Modification (Not a Decrease in Scope)

For modifications that are not a decrease in scope — extending the term, adding space without meeting the separate-contract test, or changing only the consideration — the lessee remeasures the lease liability using a revised discount rate and adjusts the ROU asset by the same amount as the liability remeasurement. No gain or loss is recognized in this case; the entire effect flows through the ROU asset, using the same mechanics described in Part 3 for other remeasurement events.

Reassessing Classification at Modification

Every modification that is not accounted for as a separate contract requires the lessee to re-run the classification test from Part 1 as of the modification date, using the remaining lease term and the fair value of the underlying asset at that time. It is entirely possible — and not uncommon — for a lease that started as an operating lease to reclassify as a finance lease after a substantial modification, or vice versa. When classification changes, the lessee applies the new classification prospectively from the modification date.

Common Pitfalls

Two mistakes show up repeatedly in practice. The first is treating every amendment as a “separate contract” because it is documented in a separate amendment letter — the accounting test looks at substance (additional right of use, priced at standalone value), not the form of the paperwork. The second is forgetting to reassess classification after a modification, which can leave a lease misclassified for the remainder of its term if the modification was substantive enough to change the economics.