See how an ESPP lookback changes the purchase price.

How a lookback works

A lookback applies the plan’s stated discount to the lower of the applicable offering-start FMV and purchase-date FMV. Without a lookback, this illustration applies the same stated discount to the purchase-date FMV.

Illustrative example

Offering-start FMV is $40.00, purchase-date FMV is $45.00, and the stated discount is 15%. The lower anchor is the offering-start FMV. The illustrative purchase price is $34.00 per share with the lookback and $38.25 per share without it—a $4.25 additional per-share price difference from the lookback.

What this comparison does—and doesn’t include

These are illustrative plan purchase prices per share. Actual plan terms and employer records determine the applicable grant or offering date, purchase date, FMVs, discount, and purchase price.

This tool does not calculate shares, contributions, payroll deductions, the IRC §423(b)(8) annual limit, tax, sale treatment, or future stock performance.

Educational information only—not financial, tax, or legal advice. Confirm your plan terms and records with your employer’s plan administrator and consult a qualified professional for your circumstances.

Primary sources and math authority

• 26 U.S.C. §423(b)(6), U.S. House Office of the Law Revision Counsel
• IRS Publication 525, employee stock purchase plan example
• Calculation behavior follows the reviewed ModuEquity ESPP math specification. Actual plan terms control.