Form 8949
Also: Form 8949, 8949, capital gains form
The IRS form used to report sales of capital assets, including stock, RSUs after vest, ISO shares, and ESPP shares. Totals flow into Schedule D for net capital gain or loss.
Form 8949 reports each capital asset sale during the year. Transactions are separated into short-term (held one year or less) and long-term (held more than one year) sections and further split by whether the basis was reported to the IRS by the broker (Boxes A and D) or not (Boxes B, C, E, F). Adjustments to basis are entered in column (g) with a code, such as code B for a reported basis that is too low because RSU or NSO income was already on the W-2.
Example: an employee sells 1,000 RSU shares that vested at $120 and are now $150. The broker’s 1099-B reports basis of $0 (only the purchase at vest was recorded). The correct basis is $120, the FMV at vest. On Form 8949 the employee enters the $0 basis as reported, then adjusts by $120,000 with code B to produce a $30,000 long-term capital gain.
Common mistake: accepting the 1099-B basis without the RSU or ESPP adjustment. This overstates gain by the full vesting-date value and produces a six-figure over-payment in big vest years.
Form 8949 matters at every year with equity sales and is the single most common source of RSU-related tax preparation errors.