We report extensive differential V-band photometry and high-resolution spectroscopy for the 1.14d, detached, double-lined eclipsing binary BT Vul (F0+F7). Our radial-velocity monitoring and light-curve analysis lead to absolute masses and radii of M1=1.5439+/-0.0098M_{sun}^N^ and R1=1.536+/-0.018R{sun}^N^ for the primary, and M2=1.2196+/-0.0080M{sun}^N^ and R2=1.151+/-0.029R{sun}_^N^ for the secondary. The effective temperatures are 7270+/-150K and 6260+/-180K, respectively. Both stars are rapid rotators, and the orbit is circular. A comparison with stellar evolution models from the MESA Isochrones and Stellar Tracks series shows excellent agreement with these determinations, for a composition of [Fe/H]=+0.08 and an age of 350Myr. The two components of BT Vul are very near the zero-age main sequence.