Non-league side Merstham will take on Oxford United at home in their first taste of FA Cup first-round action.
The Surrey-based club, who compete in the Isthmian League Premier Division, have already made it past five opponents to reach this stage - the latest being Ebbsfleet United whom they defeated 2-1 at the weekend.
Westfields were the lowest-ranked team in the hat for the draw, playing their football in the ninth tier of the English game, and they will face the winners of the replay between York City and Curzon Ashton.
Elsewhere, Southern League outfit Chesham have been paired with EFL side Peterborough United, while MK Dons will play host to Spennymoor Town.
FA Cup first-round draw in full:
Sheffield United vs. Leyton Orient
Millwall vs. Southend United
Dagenham & Redbridge vs. FC Halifax Town
Merstham vs. Oxford United
Taunton Town/Hemel Hempstead Town vs. Barrow
Cambridge United vs. Dover Athletic
Westfields vs. York City/Curzon Ashton
MK Dons vs. Spennymoor Town
Gillingham vs. Brackley Town
Alfreton/Gateshead vs. Newport County
Portsmouth vs. Wycombe Wanderers
Maidstone United vs. Rochdale
Bury vs. AFC Wimbledon
St Albans City vs. Carlisle United
Boreham Wood vs. Notts County
Mansfield Town vs. Plymouth Argyle
Braintree Town vs. Eastbourne Borough
Hartlepool United vs. Wrexham/Stanford
Bolton vs. Grimsby Town
Bradford City vs. Accrington Stanley
Lincoln City/Guiseley vs. Altrincham
Exeter City vs. Luton Town
Charlton Athletic vs. Scunthorpe United
Cheltenham Town vs. Crewe Alexandra
Peterborough United vs. Chesham United
Blackpool vs. Kidderminster Harriers
