What 'Date of Marriage Valuation' means when you own crypto, and a worked example
If you own crypto and you're going through a divorce, you've probably heard the phrase "date of marriage valuation" from your attorney, a blog, or a late-night Google search. The concept is straightforward: courts need to know what your crypto was worth on the day you got married, because that number determines what counts as separate property (yours before the marriage) versus marital property (up for division).
For crypto, this can become a whole project.
Why crypto makes this harder
Three reasons. First, crypto markets run 24/7 across hundreds of exchanges, so there's no official "closing price" the way stocks have one. The price of ETH on Coinbase at 11:47pm UTC might differ from Kraken at the same moment by 1–3%. Second, holdings can be scattered across hardware wallets, exchange accounts, and DeFi protocols with no consolidated statement. Third, volatility makes the specific date matter a lot more: a $200 BTC swing on a Tuesday isn't unusual, and that swing multiplied across a large holding can move a settlement by tens of thousands of dollars.
The worked example
Alex got married on June 14, 2017. On that date, Alex held:
- 2 BTC (on a Coinbase account)
- 30 ETH (on a Ledger hardware wallet)
- 5,000 USDC (listed on a personal spreadsheet)
Today, Alex is preparing for divorce proceedings. What does the date-of-marriage valuation actually look like?
Step 1: Confirm what was actually held on that date
This is harder than it sounds, and it's where most DIY attempts fall apart.
For the Coinbase BTC: Alex needs to pull historical transaction records from Coinbase, not a screenshot of today's balance, but the downloadable CSV or statement showing the account state on June 14, 2017. Coinbase provides this through their tax reporting tools. Exchange records carry weight in court because they come from a regulated, identifiable entity.
For the Ledger ETH: There's no Ledger "statement." What Alex actually needs is the Ethereum wallet address the Ledger controlled, then on-chain transaction history showing the balance on that date. Blockchain explorers like Etherscan can provide this. The blockchain is an immutable public ledger, every balance at every moment is permanently recorded. This is actually stronger evidence than an exchange statement, once properly documented.
For the 5,000 USDC: This is the item a forensic accountant would flag immediately. USDC was not announced by Circle until May 2018 and didn't launch until September 2018. It did not exist on June 14, 2017. If Alex's spreadsheet claims a USDC holding at a date when the token hadn't been created, that entry is factually impossible. In a court setting, this kind of error can undermine the credibility of the entire disclosure. A judge or opposing counsel will reasonably ask: if this entry is fabricated, what else is?
The lesson: every asset on the list needs to be verified against reality and not just copied from personal records.
Step 2: Get the historical price for each asset
On June 14, 2017:
| Asset | Quantity | Price (USD) | Source | Total Value |
|---|---|---|---|---|
| BTC | 2 | ~$2,580 | CoinGecko daily aggregate | $5,160 |
| ETH | 30 | ~$345 | CoinGecko daily aggregate | $10,350 |
| USDC | 5,000 | N/A | Did not exist | $0 (excluded) |
Total date-of-marriage valuation: $15,510
A few notes on why the details matter here. CoinGecko and CryptoCompare are the two most commonly cited aggregators in forensic crypto work. They don't always agree, differences of 1–3% on historical daily prices are normal, because each aggregator pulls from a different set of exchanges and applies its own methodology for removing outliers. Courts generally don't care about a 2% discrepancy, but your methodology footnote needs to specify which source you used and stick with it consistently across all assets. Mixing CoinGecko for BTC and CryptoCompare for ETH in the same filing is the kind of inconsistency opposing counsel will highlight.
Step 3: Choose a price methodology and document it
Did you use the daily open, daily close, or a volume-weighted average (VWAP)?
There's no universal standard. Some practitioners use the daily close (midnight UTC), some use a 24-hour VWAP, and some use the daily midpoint. What matters is that you pick one, state it explicitly, and apply it uniformly. If you used the CoinGecko daily close for BTC, use the CoinGecko daily close for ETH too.
In cases with large holdings, attorneys sometimes agree to a 30-day rolling VWAP centered on the marriage date to smooth out daily volatility. This is more common in settlement negotiations than in contested filings, but it's worth knowing about.
Step 4: Format for legal submission
The final document should include:
A header identifying the valuation date (June 14, 2017), the jurisdiction, and the party name. A per-asset table showing quantity, unit price, pricing source, and fiat total. A methodology footnote explaining the pricing approach (e.g., "All prices reflect the CoinGecko daily close in USD for the 24-hour period ending midnight UTC on June 14, 2017"). A total valuation figure. And a sources appendix listing the specific URLs or API endpoints used.
This is the deliverable a forensic accountant would produce. It's the format opposing counsel expects to see.
Common mistakes that get filings challenged
Using screenshots as evidence. A screenshot of a wallet balance is a raster image with no cryptographic verification, no metadata proving it hasn't been altered, and no chain of custody. Under Federal Rules of Evidence 901 and 1002, courts routinely reject them. Screenshots might help you locate a wallet address during early discovery, but they can't authenticate a financial claim in front of a judge.
Inconsistent pricing sources. Using CoinGecko for one asset and an exchange-specific price for another, without explaining why, gives opposing counsel an easy procedural objection.
Ignoring the "did this asset exist?" question. The USDC example above isn't hypothetical: forensic accountants report seeing impossible asset dates regularly. Any token that launched after your marriage date simply can't appear on the date-of-marriage valuation.
Confusing valuation with property characterization. Valuation answers "what was it worth?" Property characterization answers "whose is it?" - separate, marital, or commingled. These are different legal questions. If Alex bought additional BTC after the wedding using a joint bank account and deposited it into the same Coinbase account, those post-marriage purchases are commingled with the pre-marriage holdings. Untangling that requires tracing, which is a separate (and often expensive) exercise. The valuation step documented above is a prerequisite, not a substitute.
A note on DeFi positions
If holdings on the marriage date included LP tokens, staked positions, or wrapped assets, the valuation chain gets significantly more complex. An LP position on Uniswap, for example, is subject to impermanent loss - the fiat value displayed on a DeFi dashboard may not reflect what you'd actually receive upon withdrawal. Valuing these positions accurately requires reconstructing the smart contract interaction at the historical date, which is specialized forensic work. For most people with straightforward exchange or wallet holdings, the process above covers it. If you had active DeFi positions on your marriage date, that's a conversation for a forensic specialist.
What this costs when done professionally
A forensic accountant producing this exact deliverable typically charges in the low thousands: $3,000 to $7,500 for an initial assessment, more if the case involves complex tracing or DeFi positions. The underlying calculation, given access to historical pricing APIs and on-chain data, is largely deterministic. You're paying for the expert's credentials, their familiarity with evidentiary standards, and a report format that holds up under cross-examination.
Worth considering: if your family law attorney bills at $400/hour and spends five hours figuring out how to pull historical crypto prices and format them, that's $2,000 in attorney time for work that isn't really legal analysis. Knowing what the deliverable looks like means you can either verify what your attorney produces, provide a draft for them to review, or handle the mechanical parts yourself and save those hours for actual legal strategy.
If you'd rather not assemble this manually, CoinEvidence generates this exact format from a wallet address and a date.