Crypto Cost Basis Methods: FIFO, LIFO, HIFO, and Specific Identification

Key Takeaways

• IRS guidance recognizes two cost basis methods for digital assets: first-in-first-out (FIFO), which applies by default, and specific identification, which requires an affirmative, contemporaneous election.
• LIFO and HIFO are not separate IRS-named methods. They describe ordering rules — last-acquired-first or highest-cost-first — that a taxpayer can apply only by satisfying the specific identification requirements for every disposal.
• A specific identification is valid only if the units disposed of are identified at or before the time of the transaction and the identification is documented. Choosing convenient lots later, while preparing a return, generally does not qualify.
• Beginning January 1, 2025, Rev. Proc. 2024-28 ended universal, pooled cost basis tracking across every wallet and account. Basis must generally be tracked separately within each wallet or account going forward.
• Rev. Proc. 2024-28 also provided a one-time, irrevocable safe-harbor method for allocating a taxpayer's existing unused basis to specific wallets as of January 1, 2025, using either a specific-unit or a global allocation approach.
• The same set of disposals can produce materially different reported gain depending on which method and which specific lots are used — the underlying economics of the sale do not change, only which lots are treated as sold.
• The lot with the smallest reported gain is not automatically the one that minimizes total tax owed, because short-term and long-term gains can be taxed at different rates.
• This is general education, not a substitute for professional tax advice on a specific return.

Why the Cost Basis Method Matters

When a taxpayer holds crypto acquired at different times and different prices, and then disposes of only part of the position, a decision has to be made about which units were sold. That decision — the cost basis method — determines the adjusted basis used in the gain-or-loss calculation, and it can move the reported result substantially even though nothing about the sale itself changed.

Under Notice 2014-21, the IRS treats digital assets as property for U.S. federal income tax purposes, and general property tax principles apply. Property held in multiple lots at different costs has always required a lot-identification rule for partial dispositions; crypto is no exception. What makes crypto distinctive is that a single taxpayer can accumulate dozens or hundreds of lots across exchanges, wallets, staking rewards, and airdrops, often with incomplete records connecting them — which makes the choice of method, and the discipline of applying it correctly, more consequential than it typically is for a brokerage account holding a handful of stock purchases.

The method chosen also interacts with holding period. Units acquired more than one year before disposal generally qualify for long-term capital gain treatment, which can be taxed at preferential rates; units held one year or less are short-term and taxed at ordinary income rates. A method that minimizes the dollar amount of gain reported is not always the method that minimizes the tax actually owed, because the character of the gain matters as much as its size.

FIFO, LIFO, HIFO, and Specific Identification, Explained

The table below summarizes how each method orders lots for a disposal, and — importantly — which of them are independently recognized by the IRS versus which are outcomes achieved through a valid specific identification.

This distinction matters more than it might first appear. Tax software commonly offers "FIFO," "LIFO," and "HIFO" as interchangeable dropdown settings, which can create the impression that all three are equally IRS-sanctioned choices. Under IRS guidance, only two methods exist: FIFO, which is automatic, and specific identification, which is elective and comes with a documentation requirement attached to every disposal, not just a one-time software setting. LIFO and HIFO are simply descriptions of the ordering rule a taxpayer applies while making a valid specific identification — the identification requirement does not go away because a piece of software labeled the output "HIFO."

FIFO in Practice

FIFO is straightforward to apply and requires no additional documentation beyond the ordinary transaction records already needed for the ledger: it simply consumes the oldest lot first, then the next-oldest, and so on, until the disposed quantity is fully accounted for. Because FIFO is the default, a taxpayer who does not affirmatively identify specific lots for a disposal is treated as having sold FIFO-order units, whether or not that was the intent.

Specific Identification in Practice

Specific identification lets a taxpayer choose exactly which lot or lots to treat as sold, subject to two conditions: the units actually disposed of must in fact belong to the identified lot (the taxpayer cannot identify units they do not hold), and the identification must be made at or before the time of the transaction, with adequate records. A specific identification made after the fact — for example, reviewing the year's price history in April and then deciding which lots would have produced the best result — generally does not satisfy this requirement.

HIFO and LIFO orderings are simply strategies for choosing which lots to identify. A taxpayer using a "HIFO" approach is, in substance, making a specific identification of the highest-cost lot(s) available for each disposal; the same documentation and timing requirements apply as for any other specific identification.

Why the Difference Matters for Tax Owed

FIFO tends to consume the oldest, and often lowest-cost, lots first, which in a rising market typically produces the largest reported gain of the four approaches (though not always — it depends on the specific purchase history). HIFO-style identification is designed to minimize the reported gain on a given disposal by selecting the highest-basis lots available, regardless of when they were acquired. LIFO-style identification consumes the most recently acquired lots first, which tends to fall between FIFO and HIFO in a market that has trended upward over time. Because none of these outcomes are guaranteed — actual purchase history, especially with volatile assets, rarely moves in one direction — the worked example later in this guide walks through one concrete case.

Default Method vs. Affirmative Election

Understanding which method applies without action, and which requires the taxpayer to do something, is central to avoiding an unintentional FIFO result.

A practical consequence follows from this: a taxpayer who wants anything other than FIFO treatment carries the burden of making and preserving evidence of the election. Waiting until filing season to decide which lots "should" have been sold does not create a valid specific identification after the fact.

The 2025 Per-Wallet and Per-Account Basis Rule

For years, many taxpayers and tax software products applied cost basis methods on a universal, pooled basis — treating every unit of a given asset held anywhere (across every exchange account and wallet) as one combined inventory, and applying FIFO or a chosen method across that entire combined pool. That approach is no longer available for transactions from January 1, 2025 onward.

Under Rev. Proc. 2024-28, digital asset basis must generally be tracked separately within each wallet or account, rather than pooled universally across a taxpayer's entire holdings. In practice, this means a lot's basis sitting in Wallet A cannot be used to offset, or be selected for, a disposal that occurs in Wallet B — even if both wallets hold the identical asset and are owned by the same taxpayer. Each wallet or account effectively becomes its own basis-tracking unit.

This change interacts directly with the reporting regime introduced for digital-asset brokers: Form 1099-DA, required for covered transactions from January 1, 2025 onward, is filed on a per-broker, per-account basis. Per-wallet basis tracking keeps a taxpayer's own records structurally aligned with how brokers report, which supports reconciliation — but it also means that transferring assets between a taxpayer's own wallets, previously a basis-neutral non-event handled loosely by many pooled trackers, now requires more careful basis carry-over bookkeeping so the receiving wallet's per-wallet ledger correctly reflects the original acquisition date and cost.

The Rev. Proc. 2024-28 Safe Harbor for Existing Holdings

Because taxpayers who had been using universal, pooled tracking could not simply relabel their existing combined basis pool as belonging to specific wallets on January 1, 2025, Rev. Proc. 2024-28 provided a one-time safe harbor for making that transition. Under the safe harbor, a taxpayer could reasonably allocate their existing unused basis — generally, the basis in all units held as of January 1, 2025 — to the wallets and accounts actually holding those units, using either:

• Specific unit allocation: assigning basis to individual, identified units of digital assets held in a wallet.
• Global allocation: applying a consistent, written allocation rule (such as FIFO within each wallet) to distribute the pooled basis across wallets holding the same asset.

This one-time allocation is described as irrevocable and needed to be completed under the transition timeline the revenue procedure specified. A taxpayer who did not make a reasonable allocation under the safe harbor, or who cannot substantiate one, may face a more difficult reconstruction problem establishing per-wallet basis retroactively. This is an area where the specific facts — how many wallets, how the allocation was documented, whether it was done before the applicable deadline — matter a great deal, and professional review is warranted for anyone who held crypto across multiple wallets before 2025 and has not confirmed how their existing basis was allocated.

Worked Example: Same Disposal, Four Different Results

Hypothetical example — for education only.

A taxpayer holds four lots of the same asset in a single wallet, purchased at different times and prices:

Total holding: 2.0 units, total basis $84,000. On July 15, 2026, the taxpayer sells 1.0 unit (half the position) for $65,000 gross proceeds, paying a $100 disposition fee. Amount realized on the sale is $65,000 − $100 = $64,900, regardless of which lots are treated as sold. What changes with the method is which $64,900 of proceeds gets matched against which basis.

Amount realized (all methods):     $64,900

FIFO   — sells Lot A + Lot B:       basis $8,500 + $26,000 = $34,500
                                     gain  $64,900 - $34,500 = $30,400  (long-term)

LIFO   — sells Lot D + Lot C:       basis $31,000 + $18,500 = $49,500
                                     gain  $64,900 - $49,500 = $15,400  (long-term)

HIFO   — sells Lot D + Lot B:       basis $31,000 + $26,000 = $57,000
                                     gain  $64,900 - $57,000 = $7,900   (long-term)

Specific ID (taxpayer selects
Lot A + Lot D at trade time):       basis $8,500 + $31,000 = $39,500
                                     gain  $64,900 - $39,500 = $25,400  (long-term)

Every scenario above happens to produce a long-term gain in this example, because all four lots were held more than one year as of the sale date, so holding period does not create additional divergence here. The gain reported still ranges from $7,900 to $30,400 — a difference of $22,500 — purely as a function of which lots are identified, with no change to the amount actually received from the sale. This illustrates why the method (and, for anything other than FIFO, the taxpayer's contemporaneous identification and documentation) is not a minor mechanical detail: it is one of the largest levers on the reported result of an otherwise identical transaction.

In a scenario where some lots are short-term and others long-term, the "lowest gain" method is not automatically the "lowest tax" method — a HIFO-style selection that happens to consume a short-term lot can produce a smaller dollar gain that is taxed at a higher rate than a larger long-term gain from a different lot combination. Evaluating the after-tax result, not just the reported gain, generally requires modeling both the gain amount and the character of each candidate lot combination.

Misconceptions vs. Reality

Practical Checklist Before You Rely on a Cost Basis Method

• Confirm which method was actually applied to each disposal in your records — do not assume a software default matches your intent.
• If you intend anything other than FIFO, verify that a specific identification exists for each disposal, made at or before the time of the transaction, not reconstructed afterward.
• Keep the identification record itself: the lot's acquisition date, quantity, basis, and a timestamp showing when the identification was made.
• Confirm your basis tracking is organized per wallet and per account for transactions from January 1, 2025 forward — not pooled across your entire portfolio.
• If you held crypto across multiple wallets before 2025, confirm how your pre-2025 basis was allocated to specific wallets under the Rev. Proc. 2024-28 safe harbor, and retain that allocation documentation.
• When comparing methods for an upcoming disposal, model both the dollar amount of gain and its short-term/long-term character before assuming the lowest-gain option is the lowest-tax option.
• Reconcile any Form 1099-DA basis figures against your own per-wallet lot records rather than assuming the form reflects your chosen method correctly.
• Document any change in method or allocation approach between tax years, and consult a tax professional before making a change that could raise consistency or IRS-consent questions.
• Retain original, unmodified source records (exchange exports, wallet histories) that support every lot's acquisition date and basis, in addition to the processed ledger.

Sources and Methodology

This guide is based on publicly available IRS guidance and regulatory materials as of August 2026. Key sources include:

• IRS Notice 2014-21: Establishes that virtual currency is treated as property for U.S. federal tax purposes, applying general property tax principles, including basis and gain/loss concepts, to digital assets.
• IRS digital-asset FAQs: Published IRS guidance addresses lot identification, including that FIFO applies absent a valid specific identification, and describes the requirements for a specific identification to be respected.
• Rev. Proc. 2024-28: IRS revenue procedure ending universal, pooled cost basis tracking for digital assets and requiring basis to be tracked per wallet and account beginning January 1, 2025, along with a one-time safe harbor for allocating existing unused basis to specific wallets.
• Form 1099-DA materials: IRS forms, instructions, and related regulations governing broker reporting of digital-asset transactions for covered transactions on or after January 1, 2025, reported on a per-broker, per-account basis.

This content was reviewed by the Swoopr Markets Education Team in August 2026 and reflects U.S. federal tax guidance available at that time. Tax law and IRS guidance change; verify current guidance, and consult a qualified tax professional, before relying on any information in this guide for an actual return.

Cost Basis Method FAQs

Related Reading

• Crypto Taxes and Recordkeeping: Complete U.S. Guide — the full pillar guide covering taxable events, ledger fields, the TRACE framework, and Form 1099-DA reconciliation.
• The Wash-Sale Rule and Crypto — how loss-harvesting interacts with cost basis lot selection.
• Comparing Crypto Tax Software — what to check before trusting a tool's FIFO, LIFO, or HIFO output.
• Form 1099-DA Explained — what broker-reported basis figures do and do not cover under the 2025 reporting regime.