Weighted average cost (WAVG / ACB): what it means for crypto tax

Weighted average cost pools all units of an asset into a single average cost per unit, used as the basis for every disposal. Known as the Average Cost Basis (ACB) in some countries, it is the required method in several jurisdictions.

General information, not tax advice. Crypto tax rules differ by country and change over time, verify against your country's guidance or a qualified advisor.

An example

Buy 1 coin at 1,000 and 1 at 3,000, and your average basis is 2,000 per coin, used for any sale regardless of which you sell.

Why it matters for your tax

Averaging removes the choice of which lot to sell, which is simpler but gives less room to optimise. Where your country mandates it, no other method applies.

CryptaTax handles this automatically across your wallets and exchanges, so the concept is applied consistently without you tracking it by hand. Try the crypto tax calculator →

Related terms

• FIFO
• Cost basis method
• Cost basis guide

See the full crypto tax glossary for every term, or the crypto tax guides for how they fit together.

Understanding Weighted average cost (WAVG / ACB): what it means for crypto tax in crypto records

Weighted average cost (WAVG / ACB): what it means for crypto tax: records to review

Weighted average cost (WAVG / ACB) is a method for calculating the cost basis of an asset when you sell or dispose of it. Instead of tracking the exact purchase price of each individual unit, you pool all your acquisitions of the same asset into a single average cost per unit. This average cost is then used to determine your gain or loss on every disposal, regardless of which specific units you sell. The method is also known as the Average Cost Basis (ACB) in some jurisdictions, and it is the mandated approach for crypto tax reporting in several countries.

Weighted average cost (WAVG / ACB): what it means for crypto tax: a record-based example

To illustrate, imagine you buy 1 BTC at $10,000, then later buy another 1 BTC at $20,000. Your total cost is $30,000 for 2 BTC, giving a weighted average cost of $15,000 per BTC. If you then sell 0.5 BTC for $12,000, your cost basis for that sale is 0.5 * $15,000 = $7,500, resulting in a taxable gain of $4,500. If you had used FIFO (first-in, first-out), the cost basis would have been $5,000 (from the first purchase), leading to a higher gain of $7,000. The weighted average smooths out price volatility and can simplify record-keeping, especially for frequent traders.

Weighted average cost (WAVG / ACB): what it means for crypto tax: related concepts

It's important to distinguish WAVG from other methods like FIFO, LIFO (last-in, first-out), or specific identification. FIFO assumes you sell the oldest units first, which can lead to higher gains in a rising market. LIFO assumes you sell the newest units first, which can defer taxes but may not be allowed in all jurisdictions. Specific identification lets you choose which units to sell, offering flexibility but requiring meticulous tracking. WAVG, by contrast, treats all units as interchangeable, which is often simpler but may not be optimal for tax planning if you want to control the timing of gains or losses.

Weighted average cost (WAVG / ACB): what it means for crypto tax: practical next step

For practical next steps, if you are in a jurisdiction that requires or allows WAVG, you should maintain a ledger of all your crypto transactions, including dates, amounts, and values in your local currency. Use a reliable crypto tax software that supports WAVG calculations, or set up a spreadsheet to compute the average cost after each acquisition. Be aware that some exchanges provide cost basis reports, but they may not use WAVG, so verify the method. Also, consider the impact of fees: include transaction fees in your cost basis to be accurate. Finally, keep records for at least the required period in your country, and consult the tax authority's guidance to ensure compliance. Remember, this is not financial advice, but a general explanation to help you understand the concept.

A careful next step

Before acting on this term, return to the original record and write down the question it raises: what changed, which source proves it, and whether another related concept describes the event more accurately. Keep that note with the export or wallet evidence. It makes a later review faster and avoids turning a short label into an unsupported conclusion about tax, accounting or reporting.