Your ASIC has been humming in the spare room for months. The electricity bill has reduced the profit.
Home miners can usually claim evidenced extra costs of earning cryptoassets. They cannot usually claim a share of all household bills.
Treatment depends on whether the activity is miscellaneous income or a trade.
Measure the miner's added electricity use and create a claim HMRC can check.
Record kWh and the tariff
Use a suitably rated smart plug to record each miner’s monthly kWh. Then multiply that figure by the unit rate on the bill for the same period.
For example, 620 kWh at 24p per kWh gives £148.80. If no plug is available, calculate wattage ÷ 1,000 × operating hours × tariff.
Actual readings are stronger evidence. The typical error is using the bill's total cost, including standing charges.
Keep the readings with each bill.
For home mining, the clearest electricity claim is measured miner kWh × the applicable bill-period unit rate. Back it with energy bills, smart-plug readings and operating dates.
Decide how HMRC may view mining
Occasional mining may be miscellaneous income. A regular, organised and commercial operation with a genuine profit aim may be a trade.
HMRC considers all the facts. These include scale, regularity, equipment and planning.
The distinction is clear in theory, but classification often takes longer than the maths. A miner with one ASIC can still need advice if the facts point both ways.
Home-mining tax decision path
Mining rewards received
→
Small or occasional?
→
Consider miscellaneous income
Regular, organised and commercial?
→
Assess trade and capital allowances
→
Separate running costs from household spending
Separate costs caused by mining from costs you would pay anyway.
Sort each receipt into the right column
Pool fees and repairs are easier to claim when records link them directly to mining. Keep the statement or receipt with the mining date.
Internet needs a fair business-only share. Ordinary rent, mortgage capital repayments, household heating and general broadband are usually private costs.
The most frequent mistake is claiming costs that would exist without the miner. Think of the extra electricity as water used by a separate tap.
| Cost | Usual treatment | Evidence | Main risk |
|---|
| Added electricity | Usually claimable | kWh and tariff bill | Whole-bill estimate |
| Pool fees | Usually claimable | Pool statement | Missing dates |
| Dedicated extraction fan | Facts-dependent | Receipt and use note | Private cooling |
| ASIC or GPU purchase | Usually capital | Invoice and serial number | Calling it a running cost |
| Rent or mortgage | Usually not claimable | Apportionment records | Private living cost |
Compare actual costs with £1,000
Compare actual allowable expenses with the £1,000 Trading Allowance or miscellaneous income allowance before choosing.
Evidenced costs of £1,350 may beat the allowance. Costs of £260 may make the allowance simpler.
You cannot claim both for the same income. This comparison takes between 10 and 20 minutes when receipts are already sorted.
For a home-mining cost review, split household electricity evidence into normal domestic use and the miner's extra use. Home mining electricity costs should use smart-plug kWh readings, power use, operating hours and the bill-period tariff.
Pool fee receipts, mining equipment repairs and a dedicated ventilation fan may be direct costs. They must relate only to mining.
A business-only internet share must be fair and evidenced. General broadband, household heating, rent and mortgage payments remain private.
A distinct, supportable business element may change that result. However, ASIC running costs differ from buying the ASIC itself.
Buying the ASIC is normally capital expenditure.
Treat ASIC and GPU purchases as capital
Review hardware as capital expenditure before entering it as an expense.
Check capital allowance eligibility
ASICs and GPU rigs are often plant and machinery. Capital allowances may apply instead of an immediate expense deduction.
This can include the Annual Investment Allowance where available. Save invoices, payment proof, model and serial number.
Adjust fairly for any private use. A home rig used for personal testing needs a clear private-use note.
Keep income and CGT separate
Value every mining reward in pounds sterling when received. Record its timestamp, amount, wallet or pool account and valuation source.
That value is relevant for Income Tax. A later sale, swap or spend can create Capital Gains Tax.
Do not deduct electricity, pool fees or hardware costs twice. The usual error is mixing the Income Tax record with the later CGT record.
For most home miners, record each reward in GBP on receipt. Claim only proven running costs, then keep hardware separate for capital allowance review.
This does not guarantee capital allowances. They usually depend on a qualifying trade and the facts of the activity.
If mining is miscellaneous income, do not assume the same relief applies. Keep both records before you file your Self Assessment return.
Worked example: A home miner receives rewards worth £2,400 when the pool credits them. The miner uses the GBP market value at each timestamp.
During the same tax year, readings and bills support £900 of extra electricity. Pool fee receipts total £120. Equipment repairs cost £80.
Actual revenue expenses are £1,100. This leaves £1,300 taxable income.
This is better than the £1,000 Trading Allowance. That allowance would leave £1,400 taxable.
The rig purchase is considered separately. The mined coins are later sold for £3,000.
The GBP amount already taxed as income forms part of their CGT cost basis. This follows the applicable cryptoasset matching rules.
The same £1,100 of running costs is not deducted again.
Capital allowances need particular care in a Bitcoin mining tax UK calculation. An ASIC or GPU may be plant and machinery for a qualifying mining trade.
Mining income alone does not make the purchase an immediate deduction. It also does not guarantee Annual Investment Allowance.
If HMRC sees the activity as miscellaneous income, do not assume capital allowances apply in the same way. Personal tax advice may be needed here.
Keep the invoice, serial number, payment record and date it was first used. Also record any private-use share.
Review the current rules before claiming relief. Hardware treatment should follow the trade assessment.
It should not follow the retailer's or pool's label.
Build an HMRC-ready mining record pack
Build one dated record pack so each number on your return can be traced.
Keep pool statements and wallet transaction IDs. Keep GBP valuations at receipt and energy bills.
Keep tariff notices, smart-plug exports and uptime logs. Keep hardware invoices, repair receipts and payment evidence.
Keep these records for the required Self Assessment record-keeping period. Missing timestamps are often harder to rebuild after a pool changes its dashboard.
Enter each cost once only. Use clear categories such as electricity, pool fee, repair, internet share or capital asset.
Before filing, check total income. Then check actual expenses or the allowance.
Check capital allowance treatment and later disposals. A simple spreadsheet with one row per reward makes this check far easier.
A case often seen involves a miner with bills but no operating dates. The electricity claim then becomes much harder to support.
This guidance is less relevant if you buy or stake cryptoassets rather than mine them. It is also less relevant if you mine through a company or run a larger commercial operation. Seek tailored advice if rewards come through employment or you have cross-border tax residence issues. A UK crypto tax professional can review those facts.
Frequently asked questions
Can I claim my home mining electricity?
Yes, where you can show the miner’s extra use and the applicable tariff. Smart-plug kWh readings multiplied by the unit rate give strong evidence.
Do I have to report mined bitcoin to HMRC?
Usually, you may need to report taxable mining income through Self Assessment. This depends on your facts and allowances.
Record each reward’s GBP value when received.
Can HMRC accept capital allowances on mining rigs?
Possibly, if the equipment qualifies as plant and machinery. The relevant conditions must also be met.
ASICs and GPUs are not automatically ordinary expenses.
Is the £1,000 allowance always better?
No. It is better only when it gives a better result than actual allowable expenses.
You cannot claim both for the same income.
File a claim you can explain
File only the figures you can trace from reward to receipt. Measured electricity, dated pool records and clear hardware treatment give a defensible starting point.
The choice between miscellaneous income and a trade may need tailored advice. This is most true where regular home mining has grown beyond one or two machines.
Related sources
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