Cian Bolger scored twice as Fleetwood set up a reunion with Leicester's Jamie Vardy by ending Hereford's run in the FA Cup with a 2-0 win at Edgar Street.
Fleetwood took the lead from their second corner of the game in the 10th minute, Bolger rising to head home a George Glendon cross.
Hereford should have levelled in the 21st minute when Keyon Reffell shot wide after Garyn Preen and John Mills had set up the shooting chance.
The home side's hopes of a second-half comeback were dashed by a repeat of the first goal with Bolger again leaping above a static defence to head in a Glendon corner with 58 minutes gone.
Hereford tried hard to claw their way back into the replay and two efforts from Calvin Dinsley, their goal hero at Highbury in the first match between the sides, just cleared the bar.
The Bulls searched for a consolation but Fleetwood held on to secure a third-round meeting with Premier League club Leicester and Vardy, who joined the Foxes for £1 million when the Cod Army were non-league.