Since forward pricing formulas are used to evaluate futures, the question arises: are futures and forwards priced the same?

Theoretically, in the long run, it is said that a futures contract should be slightly more attractive than a forward contract with the same terms.

The reasoning goes like this:

If we assume that the underlying asset price is positively correlated with interest rates, then the holder of a long futures contract gains when the asset price rises. These gains can be reinvested at an above-average return. On the other hand, if the underlying asset price falls, the futures holder suffers immediate losses, which can be financed at a below-average interest rate. The same cannot be said about a forward contract, since daily changes in gains and losses have no impact there.

Therefore, when interest rates are positively correlated with the underlying asset price, the price of a long futures contract should be slightly higher than the price of a long forward contract, and vice versa when the correlation is negative.

However, if the maturity of the futures and forward contracts is only a few months, the difference in their prices is theoretically so small that it can safely be ignored. In practice, though, the difference may result from other important factors — taxation mechanisms, differences in liquidity, or default risk.

P.S.
Difference:

FeatureFuturesForwards
Trading VenueExchange-traded (standardized contracts)Over-the-counter (OTC), privately negotiated
Contract TermsStandardized (size, maturity, settlement date)Customized to parties’ needs
LiquidityHighly liquid due to standardizationLess liquid, depends on counterparty
SettlementMarked to market daily (daily gains/losses settled)Settlement at maturity (single cash flow at end)
Counterparty RiskLow, exchange clearinghouse guarantees performanceHigh, depends on counterparty creditworthiness
Pricing ImpactAffected by daily margining → convenience of reinvestment or financingNo daily margining, profit/loss realized only at maturity
Typical UseHedging, speculation, arbitrage with standard contractsCustomized hedging, matching specific exposures
RegulationHeavily regulated by exchangesLess regulated, private agreements

Source: Options, Futures & Other Derivatives – John C. Hull