UK Employer
If your employer pays you in cryptoassets, the sterling equivalent at the date of receipt is taxable employment income, subject to income tax and national insurance (NI) contributions.

Readily convertible assets (RCAs)

Where the cryptoasset tokens received as employment income are a readily convertible assets (RCAs), such as Bitcoin, the employer is required to operate PAYE on this employment income, using their best estimate of the sterling value of the tokens at the date of receipt on the payslip, to collect the income tax and NI.
HMRC guidance at CRYPTO21100 states that cryptoassets are RCAs if trading arrangements exist, or are likely to come into existence, in accordance with section 702 of the Income Tax (Earnings and Pensions) Act 2003.
Exchange tokens like Bitcoin can be exchanged on one or more token exchanges in order to obtain an amount of fiat money. On that basis, it is HMRCโ€™s view that โ€˜trading arrangementsโ€™ exist, or are likely to come into existence at the point cryptoassets are received as employment income.

Non-readily convertible assets (Non-RCAs)

Cryptoassets received as earnings from employment, which do not meet the definition of RCAs, are still subject to income tax and NI, but employers do not have to operate PAYE.
The individual must declare and pay HMRC the income tax due on any amount of employment income received in the form of cryptoassets (using the employment pages of a Self Assessment tax return).
The employer should treat the payment of cryptoassets as payments in kind for NI purposes, and pay any Class 1A NI contributions to HMRC.