Cryptocurrency received for services you provide is ‘income’ and may be liable to tax and national insurance contributions (NIC).
If due and if the tokens are readily convertible assets, these must be paid before the crypto is paid to you. Tax and NIC paid on your behalf by your employer must be reimburse within 90 days of the end of the tax year.
If due and if the tokens are not readily convertible assets, your employer may pay the tax and NIC, but if they don’t, you will need to make arrangements to pay it via self assessment.
Tokens received from mining if you are not trading are treated as other taxable income. This is also the way rental income paid in tokens will most likely be treated.
A self assessment tax return will need to be completed unless the crypto is worth less than £1000 or if total of untaxed income is less than £2500.
Note that you have to keep records of every token received regardless of the tax or NI contributions paid. When tokens are sold, capital gains tax may be due.