Deciphr Academy
Track 6 · Module 30 · Lesson 7 of 7 · 8 min read

What should a company's finance lead prepare for its crypto taxes?

Short answer

Company tax rules are not the same as the rules for individuals. As of October 2026, UK companies pay Corporation Tax on their gains, with slightly different pooling rules, and US corporations figure tax at a flat 21% and can deduct capital losses only against capital gains.1,2,3 So a finance lead's main job is a complete, well-sourced record of every event, and a clear list of questions for a qualified tax adviser.4,5

Maya's recordsdate and timeunits, in or outvalue at the timeprice sourcefees and walletsQuestionswhich rules apply?Tax adviserdecides the taxCompany rules are not the individual rulesHer job: the file and the questions
Fig. 7. Maya's job is the file and the questions. The tax answers come from Brindlecove's adviser.
General education, not tax advice

Brindlecove, its numbers and its people are made up. The worked example below is an illustration of arithmetic, not a statement of how any real company is taxed. Company tax depends on the country, the company and its facts. Rules change. Ask a qualified tax adviser.6,3

Why the individual rules don't simply carry over

Most of this module describes the rules for individuals. Companies are taxed under their own rules, and the differences matter.1,3

UK. HMRC says companies pay Corporation Tax on their profits and gains. If a company's crypto activity is not trading, and is not taxed under another rule, a gain would typically be charged to Corporation Tax as a chargeable gain.1 The pooling rules are slightly different too.2 Both start with a same-day rule. After that, for individuals, a sale is matched with the same token bought in the next 30 days. For a company, a sale is matched with the same token bought in the previous nine days, when the sale comes within ten days of the purchase.7,2 HMRC adds that a business may face several taxes, and it will look at each case on its own facts.6

US. IRS Publication 542 says corporations figure their tax by multiplying taxable income by 21%.3 A corporation can deduct capital losses only up to its capital gains, and carries any excess to other years.3 An individual, by contrast, can deduct up to $3,000 a year of net capital loss from other income.8 The digital asset question appears on the US corporate return, Form 1120, as well as on Form 1040.9

So a worked example for an individual can mislead a company. That is why Maya uses the rules in this module only to sort events and gather records.6

Maya's file

Maya builds one record for every crypto event, using the lists from lesson 5:9,4

Field Why it is there
Type of crypto, date and time Both authorities ask for them, and the IRS asks for the time9,4
Number of units, and in or out Needed for every gain and every pool9,4
Value in dollars at the time, and the price source Value at the time sets income and gains5,4
Price paid and fees, for every purchase Fees are part of the cost basis10,11
Wallet or account, and its address In the US, units are matched within each wallet; HMRC asks for wallet addresses10,4
What the event was: sale, swap, payment, reward, fee or move It decides whether it is a disposal, income or neither9,12
How each value was worked out HMRC asks for the valuation method13
Bank statements They show the money in and out4

An illustration only: one US-style gain

To check her numbers, Maya works one sale the way the IRS FAQs describe for individuals. This is an illustration of the arithmetic only. It does not say how Brindlecove is taxed.10

Step Working Result
Basis of 40 ETH bought on 10 February 2026 $100,000 price + $200 fee10 $100,200, or $2,505 per ETH
Amount realized on 3 ETH sold on 20 August 2026 $9,000 − $30 fee10 $8,970
Basis of the 3 ETH sold 3 × $2,50510 $7,515
Gain $8,970 − $7,51510 $1,455
Holding period 10 February to 20 August 2026 is less than one year8,14 Short-term, for an individual

Under the IRS default (oldest first), the 3 ETH come from the 10 February purchase, because the reward ETH arrived later, so each has a $2,505 basis.10 And the long-term rates in lesson 3 are rates for individuals: Publication 542 says corporations figure their tax by multiplying taxable income by 21%.8,3

The tax basis in this file is not the same as the carrying amount in a company's accounts: under ASU 2023-08, the US accounting rule that Module 29 covers, crypto assets that meet its tests are measured at fair value each reporting period.15,10

Questions for the adviser

Maya's last page is a list of questions, each tied to a rule she found.6

  1. Which US taxes apply to Brindlecove, and could any other country tax it too?3,6
  2. Were the staking rewards income when they arrived, and at what value? The IRS ruling she read is written for cash-method taxpayers.16
  3. Is the airdrop income when received, or only taxed when sold?17,18
  4. Which units does each sale use: chosen units or oldest first? (If it were taxed in the UK, a pool.)10,7
  5. Is the ETH used to pay network fees a disposal each time?19
  6. Do the 2,000 USDC paid to the contractor count as a disposal of USDC?19,12
Our viewA good tax file is boring: every event, with a date, a value and a source. A boring file lets the adviser spend time on the real questions.
Sources
  1. CRYPTO41050: Cryptoassets for businesses: Corporation Tax: introduction. HM Revenue & Customs (HMRC), Cryptoassets Manual, manual last updated 28 November 2025; checked 24 October 2026.
  2. CRYPTO41350: Cryptoassets for businesses: Corporation Tax on Chargeable Gains: pooling. HM Revenue & Customs (HMRC), Cryptoassets Manual, manual last updated 28 November 2025; checked 24 October 2026.
  3. Publication 542 (01/2024), Corporations. US Internal Revenue Service (IRS), January 2024; page last reviewed or updated 30 April 2026.
  4. CRYPTO10400: Introduction to cryptoassets: record keeping. HM Revenue & Customs (HMRC), Cryptoassets Manual, manual last updated 28 November 2025; checked 24 October 2026.
  5. Frequently asked questions on digital asset transactions (Part II): income, records and where to report. US Internal Revenue Service (IRS), FAQs added 15 December 2025; page last reviewed or updated 29 June 2026; checked 24 October 2026.
  6. CRYPTO40050: Cryptoassets for businesses: which taxes apply. HM Revenue & Customs (HMRC), Cryptoassets Manual, manual last updated 28 November 2025; checked 24 October 2026.
  7. CRYPTO22200: Cryptoassets for individuals: Capital Gains Tax: pooling. HM Revenue & Customs (HMRC), Cryptoassets Manual, manual last updated 28 November 2025; checked 24 October 2026.
  8. Topic no. 409, Capital gains and losses. US Internal Revenue Service (IRS), page last reviewed or updated 24 September 2026; checked 24 October 2026.
  9. Digital assets. US Internal Revenue Service (IRS), page last reviewed or updated 2 September 2026; checked 24 October 2026.
  10. Frequently asked questions on digital asset transactions (Part II): gains, losses, basis and holding periods. US Internal Revenue Service (IRS), FAQs added 15 December 2025; page last reviewed or updated 29 June 2026; checked 24 October 2026.
  11. CRYPTO22150: Cryptoassets for individuals: Capital Gains Tax: allowable expenses. HM Revenue & Customs (HMRC), Cryptoassets Manual, manual last updated 28 November 2025; checked 24 October 2026.
  12. CRYPTO22100: Cryptoassets for individuals: Capital Gains Tax: what is a disposal. HM Revenue & Customs (HMRC), Cryptoassets Manual, manual last updated 28 November 2025; checked 24 October 2026.
  13. CRYPTO23000: Cryptoassets for individuals: valuation. HM Revenue & Customs (HMRC), Cryptoassets Manual, manual last updated 28 November 2025; checked 24 October 2026.
  14. Publication 544 (2025), Sales and Other Dispositions of Assets. US Internal Revenue Service (IRS), for use in preparing 2025 returns; page last reviewed or updated 30 April 2026.
  15. Accounting Standards Update No. 2023-08, Intangibles—Goodwill and Other—Crypto Assets (Subtopic 350-60): Accounting for and Disclosure of Crypto Assets, Summary. Financial Accounting Standards Board (FASB). Read from the FASB's own file store, December 2023; checked 24 October 2026.
  16. Rev. Rul. 2023-14: staking rewards (Internal Revenue Bulletin 2023-33). US Internal Revenue Service (IRS), 14 August 2023.
  17. Rev. Rul. 2019-24: hard forks and airdrops (Internal Revenue Bulletin 2019-44). US Internal Revenue Service (IRS), 28 October 2019.
  18. CRYPTO21250: Cryptoassets for individuals: Income Tax: airdrops. HM Revenue & Customs (HMRC), Cryptoassets Manual, manual last updated 28 November 2025; checked 24 October 2026.
  19. Frequently asked questions on digital asset transactions (Part II): sales, swaps, payments, gifts and transfers. US Internal Revenue Service (IRS), FAQs added 15 December 2025; page last reviewed or updated 29 June 2026; checked 24 October 2026.

General education built from the publicly available sources listed above. Not financial, legal, tax or investment advice. Naming a company, project or regulator is not an endorsement either way. Last checked 2026-10-24. Terms and disclaimer.