The forward rate for EUR/USD is given by:

$F = S \left( \frac{1 + i_{USD}}{1 + i_{EUR}} \right)^T$

$= 1.3261 \times \left( \frac{1.02}{1.03} \right)^{0.5} = 1.3196$

This formula is derived from Interest Rate Parity (IRP), which states that the forward exchange rate should compensate for the interest rate differential between two currencies to prevent arbitrage opportunities.