Bitfinex lending taxes: what your accountant actually needs
Margin funding interest is taxable income in most jurisdictions, and exchanges don’t hand you a filing-ready statement for it. This page explains the typical treatment in the US and Germany, why the correct number comes from the Bitfinex funding ledger (not your dashboard balance), and what an export needs to contain so your accountant stops charging you hourly to reconstruct it.
This is not tax advice. Tax treatment depends on your personal circumstances and changes with legislation and court rulings. Confirm everything on this page with a licensed tax professional in your jurisdiction before filing.
The number that matters comes from the funding ledger
Your taxable interest is the sum of the actual funding payments credited to your account during the tax year — every payment, minus Bitfinex’s fee, on the day it settled. That lives in the Bitfinex ledger as individual entries, not in any single balance figure. Reports built from anything else (screenshots, estimated APR, wallet-balance deltas) will not survive a query from the tax office. Stratum builds its reports by reconciling entry-by-entry against the funding ledger, which is also why the totals match what Bitfinex itself would show an auditor.
US: ordinary interest income (Schedule B / Schedule 1)
For US taxpayers, margin funding interest is generally treated as ordinary income in the year it is credited — the same bucket as bank interest, not capital gains. Depending on your filing situation it is typically reported on Schedule B (interest and ordinary dividends) with flow-through to Form 1040, or on Schedule 1 as other income; your preparer decides which fits your return.
Stratum exports a year-total and per-payment breakdown as CSV (Schedule-B style line items), PDF, and TurboTax TXF — the TXF file imports as one interest-income record (refcode N287, Schedule B) so TurboTax users don’t retype anything. Amounts are reported in USD using the rates at credit time.
Germany: Anlage KAP or Anlage SO? It depends on what you lend
German treatment is genuinely nuanced, and getting the form wrong is a common mistake. Two positions exist, and which one applies depends on what you lend and how your advisor classifies the activity:
Anlage KAP (§20 EStG, capital income)
Classic interest on capital — the natural fit when what you lend is fiat currency (for example USD margin funding), which produces foreign capital income with no German withholding. Capital income above the saver’s allowance is taxed at the flat 25% Abgeltungsteuer plus solidarity surcharge.
Anlage SO (§22 Nr. 3 EStG, sonstige Leistungen)
The German Federal Ministry of Finance letter of 10 May 2022 on virtual currencies treats income from lending crypto assets (including stablecoins like USDt) as "sonstige Leistungen" — other income, filed on Anlage SO and taxed at your personal rate, with a €256/year exemption threshold. Many advisors apply this to stablecoin funding.
In practice: USD funding leans KAP, UST (USDt) funding leans SO under the BMF letter, and mixed books may need both. Stratum’s German export is a year-summary of funding interest with the per-payment ledger behind it — usable as the input for either form. Show it to your Steuerberater and let them pick the line; do not pick it based on a marketing page, ours included.
What Stratum exports
CSV (Schedule-B style)
Every funding payment as a line item: date, currency, gross, Bitfinex fee, net, USD value at credit time.
TurboTax TXF
One interest-income record (N287, Schedule B) that TurboTax imports directly.
German year summary
Year total of funding interest with the full payment ledger behind it — the input your Steuerberater needs for Anlage KAP or Anlage SO.
PDF report
Human-readable year report, reconciled to the Bitfinex funding ledger, suitable for handing to a preparer or an auditor.
Frequently asked questions
Is Bitfinex lending interest taxable?
In most jurisdictions, yes — it is income in the year it is credited to your account, regardless of whether you withdraw it from Bitfinex. The US treats it as ordinary interest-type income; Germany taxes it either as capital income (Anlage KAP) or other income (Anlage SO) depending on classification. Always confirm with a professional.
Will Bitfinex send me a tax form?
Don’t count on it. Bitfinex is not a US broker issuing 1099-INTs for funding interest, and no German form arrives either. The data exists in your account’s funding ledger — extracting and reconciling it is exactly the job a report tool does.
Anlage KAP or Anlage SO for Bitfinex funding — which is correct?
It depends on what you lend and your advisor’s reading. Fiat (USD) interest fits the Anlage KAP capital-income pattern; the BMF letter of 10 May 2022 points crypto and stablecoin lending income to Anlage SO (§22 Nr. 3 EStG). Bring the year summary and payment ledger to a Steuerberater — the form choice is theirs to make, not a bot’s.
Are Bitfinex’s funding fees deductible?
Bitfinex takes its fee from each interest payment before crediting you, so reporting the net credited amount already accounts for it in most treatments. Stratum’s exports show gross, fee, and net per payment so your preparer can apply whichever presentation your jurisdiction expects.
Can I deduct the bot subscription itself?
Sometimes — for example as an expense against sonstige Leistungen income in Germany, or for US filers depending on how the activity is characterized. It is a genuinely case-specific question; ask your preparer and keep the invoices (Stratum emails them monthly).
Can I generate reports for past years?
Yes — reports are built from the Bitfinex ledger history your API key can read, so previous calendar years can be exported as long as the data is within Bitfinex’s retention. Useful if you are filing late or amending.
Get a filing-ready report instead of a spreadsheet weekend
Connect a read-capable API key and export CSV, TurboTax TXF, a German year summary, or PDF — every number reconciled to the Bitfinex funding ledger. Works on the trial; your accountant will notice the difference.