Crypto Cost Basis FIFO vs HIFO vs Specific ID 2026 Comparison Calculator

Crypto cost basis is the original purchase price plus fees paid for digital assets. When you sell, basis determines your taxable gain or loss. The IRS classifies crypto as property under Notice 2014-21, so each disposition triggers a capital gain/loss event. The cost basis method you choose — FIFO, LIFO, HIFO, or Specific Identification — directly changes your 2026 tax bill.

How Each Method Works

FIFO (First In, First Out) — Sells oldest lots first. IRS default if you don't specify. LIFO (Last In, First Out) — Sells newest lots first; useful in falling markets. HIFO (Highest In, First Out) — Sells highest-cost lots first; minimizes gain in rising markets. Specific Identification — Hand-pick which lots to sell at the time of disposition; requires contemporaneous documentation. HIFO and Spec ID generally produce the lowest tax bill when prices have risen.

Rev Proc 2024-28 Wallet-By-Wallet Rule

Starting January 1, 2026, IRS Rev Proc 2024-28 requires taxpayers to track crypto cost basis on a wallet-by-wallet (or account-by-account) basis — not as a single universal pool. If you held 5 BTC across Coinbase, Kraken, and a self-custody wallet pre-2026, you must allocate the pre-2026 basis to a specific wallet via a Reasonable Allocation method documented before your first 2026 sale. Mixing wallets to find the best basis is no longer allowed post-2026. Failure to follow this rule can void Spec ID treatment and force FIFO across all wallets.

When To Choose Each Method

Use FIFO if your oldest lots were cheap and you want long-term gains taxed at LTCG rates. Use HIFO if recent purchases were expensive and you want to minimize current gain. Use Specific ID for maximum control — match each sale to a specific lot you choose; required by IRS Notice 2014-21 to be identified contemporaneously (before or at sale time). Use LIFO only in narrow falling-market scenarios. Lock in your method consistently across the tax year; changing mid-year invites audit scrutiny.

Common Cost Basis Mistakes

(1) Universal pooling post-2026 — illegal under Rev Proc 2024-28. (2) No contemporaneous spec ID documentation — without records before the sale, IRS defaults to FIFO. (3) Lost basis on transfers — sending BTC between your own wallets is not taxable, but you must keep basis records or risk $0 basis. (4) Missing fees in basis — exchange fees, gas fees, and acquisition fees add to basis under IRC §1012. (5) Wrong holding period — short-term (≤365 days) is taxed at ordinary rates; long-term (>365 days) gets preferential 0/15/20% LTCG rates.

Last updated May 2026. Sources cited in tool output: IRS Rev Proc 2024-28, IRS Notice 2014-21, IRC §1012, IRC §1.1012-1.