Mark-to-Market
Mark-to-market (MTM) is the daily accounting practice of revaluing a financial instrument, position, or portfolio to reflect its current fair market value rather than its historical cost or book value. In derivatives markets, it serves as the mechanism by which daily gains and losses are settled between counterparties through margin accounts.
Key takeaways
- MTM ensures that derivative positions are settled daily, preventing the accumulation of large unrealized losses.
- Futures exchanges use MTM to calculate variation margin calls, requiring the losing party to top up their margin account each trading day.
- During market stress, MTM accounting can amplify procyclical behavior as falling asset prices force asset sales, further depressing prices.
- Fair value accounting under GAAP (ASC 820) and IFRS 13 extends MTM principles to a broad range of financial assets and liabilities.
- The distinction between MTM and historical cost accounting is central to understanding reported earnings volatility at financial institutions.
Explanation
Mark-to-market accounting emerged as a cornerstone of modern derivatives markets to eliminate counterparty credit risk between the trade date and final settlement. By requiring that unrealized gains and losses be settled daily through variation margin, exchanges ensure that no participant accumulates a liability larger than a single day's price move — a risk that is covered by the initial margin deposit.
In practice, a central counterparty clearing house (CCP) calculates the MTM P&L for every open position at the end of each trading day. If a futures contract has moved against a trader, the CCP debits the corresponding amount from the trader's margin account and credits it to the account of the counterparty holding the winning position. This daily cash settlement process means that the mark-to-market value of an exchange-traded futures contract is reset to zero at the start of each new session.
Beyond futures markets, MTM valuation is required under modern accounting standards for trading securities, certain available-for-sale assets, and most derivatives carried on corporate balance sheets. Financial institutions must mark their loan books, bond portfolios, and structured products to fair value, creating earnings volatility tied directly to market fluctuations. This was a major source of controversy during the 2008 financial crisis, when critics argued that MTM rules forced banks to recognize losses on illiquid assets at distressed prices, creating a self-reinforcing downward spiral.
For hedge funds, MTM is the foundation of all daily P&L reporting to investors and prime brokers. A fund's net asset value (NAV) is itself a mark-to-market calculation that captures the liquidation value of every position at current market prices. Because performance fees are often calculated on MTM gains, the accuracy and fairness of the pricing methodology used — exchange prices, dealer quotes, or model-based valuations — is critically important to both investors and fund managers.
Formula
MTM Gain/Loss = (Settlement Price_today − Settlement Price_yesterday) × Contract Size × Number of Contracts
Example
A commodity trading firm holds a long position in 100 crude oil futures contracts (each representing 1,000 barrels). At Monday's close, the front-month price is $80.00/barrel. On Tuesday the price falls to $78.50/barrel. The daily MTM loss is (100 contracts × 1,000 barrels × $1.50) = $150,000. The clearinghouse debits $150,000 from the firm's variation margin account and credits the same amount to the counterparties holding short positions. If the firm's margin account falls below the maintenance margin threshold, it receives a margin call and must deposit additional funds by the next morning's open.
Related terms
Accumulator Bond Book Value Cash Settlement Central Counterparty Clearing Compound Option Credit Risk Exchange Expiration Date Financial Crisis Futures Contract