Reporting & compliance

Cost Basis Tracking Across Multiple Purchases

If you built your position in more than one purchase, each tranche can have its own basis, date, and holding-period clock.

What it is

An original SAFE plus a later secondary top-up, or shares bought across two different rounds, means you're holding multiple tranches — each with its own cost basis and acquisition date, even though they may show up as one combined position informally.

Why it matters for a secondary

Selling only part of your stake requires identifying which specific shares you're treated as selling. Without a specific-identification election on record, the default (FIFO — first acquired, first sold) applies automatically, which can change both your taxable gain and, critically, which tranche's holding-period clock counts for QSBS purposes.

Quick facts

Default method with no election
FIFO — earliest-acquired shares are treated as sold first
Specific identification
Must generally be documented at or before the time of sale
Why it matters for QSBS
Each tranche has its own acquisition date and holding-period clock — see QSBS & Section 1202

Common mistake: Treating a partial sale's basis as one blended average across all tranches without documenting a specific-identification election before the sale.

Frequently asked questions

Do I need special software to track this?
Not necessarily — a simple spreadsheet with purchase date, price, and share count per tranche is enough, as long as it's maintained contemporaneously rather than reconstructed later.
Can I choose which tranche to sell after the fact?
Generally no — the specific-identification election needs to be made at or before the time of sale, not decided retroactively at tax time.
Is this tax or legal advice?
No. This is independent educational content, not investment, tax, or legal advice. Tax law and thresholds change; confirm your specific situation with a qualified advisor before acting on it.