If scores were level after 90 minutes had been played, a replay would take place at the stadium of the second-named team later the same week.
Those appearing in the competition proper for the first time were Bromsgrove Rovers, Vauxhall Motors (Luton), Great Yarmouth Town, Banbury Spencer, Horsham and the re-formed South Shields.
Bromsgrove's surprise qualification marked the first time the club had progressed past the preliminary round since 1921–22.
Banbury Spencer was the only club to progress from the extra preliminary round to the competition proper, defeating Oxford City, Osberton Radiator, the team from the Cowley-based Metal & Produce Recovery Depot, Maidenhead United, Southall and Grays Athletic before losing to Colchester United in that club's historic run to the fifth round.
The 44 First and Second Division clubs entered the competition at this stage, along with Rotherham United, Queens Park Rangers and Swansea Town.
The 1948 FA Cup final was contested by Manchester United and Blackpool at Wembley Stadium on 24 April 1948.
Stanley Matthews was playing his first season for Blackpool and they led the favourites 2-1 only to lose to United, who hadn't appeared in an FA Cup final for 39 years, won 4–2, with two goals from Jack Rowley and one apiece from Stan Pearson and John Anderson.
One reporter David Pole, commented; "If United's display was as close to perfection as any team could hope to go, Blackpool's was not far behind."