What Is Proof of Reserves?
Proof of Reserves (PoR) is a cryptographic verification method that allows exchanges to prove they hold enough assets to cover all customer deposits. Using Merkle tree cryptography, exchanges can demonstrate that the total of all customer balances (liabilities) is less than or equal to the exchange's on-chain holdings (assets) — without revealing any individual customer's balance.
How Proof of Reserves Works
After the FTX collapse (where the exchange was secretly insolvent), PoR became an industry expectation. Major exchanges now publish regular PoR attestations. A complete PoR includes: a Merkle tree snapshot of all customer liabilities, on-chain addresses showing exchange asset holdings, and third-party verification that assets exceed liabilities. Some exchanges also publish liability audits by accounting firms.
Why It Matters for Traders
PoR helps traders assess exchange solvency risk — the risk that your exchange doesn't actually have your funds. When evaluating PoR: check whether it includes all assets (not just BTC), whether liabilities include both spot and derivatives obligations, and how frequently it's updated. PoR is necessary but not sufficient for safety — it shows a snapshot in time and doesn't prevent an exchange from moving assets immediately after the attestation.