The 2012–13 UEFA Champions League qualifying phase and play-off round decided 10 of the 32 teams which played in the group stage.
All draws were held at UEFA headquarters in Nyon, Switzerland.
The team that scored more goals on aggregate over the two legs advanced to the next round.
If away goals were also equal, then thirty minutes of extra time would be played, divided into two fifteen-minutes halves.
If no goals were scored during extra time, the tie would be decided by penalty shootout.
The seeding in these draws (or in any cases where the results of a tie in the previous round were not known at the time of draw) was carried out under the assumption that the higher-ranked teams of the previous round would advance to this round, which means if a lower-ranked team were to advance, it would simply take the seeding of its defeated opponent.
Prior to the draws, UEFA may form "groups" in accordance with the principles set by the Club Competitions Committee, but they were purely for convenience of the draw and for ensuring that teams from the same association were not drawn against each other, and did not resemble any real groupings in the sense of the competition.
Linfield F91 Dudelange Valletta Tre Penne Lusitanos
BATE Borisov Žilina Debrecen Maribor AEL Limassol Ironi Kiryat Shmona Željezničar Linfield[†] Skënderbeu Vardar Basel Red Bull Salzburg Helsingborgs IF Ventspils
The New Saints F91 Dudelange[†] Flora Dinamo Zagreb Partizan Sheriff Tiraspol Slovan Liberec Śląsk Wrocław Zestaponi Ludogorets Razgrad Valletta[†] Budućnost Podgorica Neftçi Shakhter Karagandy Ulisses Debrecen won 3–1 on aggregate.
Anderlecht BATE Borisov[†] F91 Dudelange[†] CFR Cluj Helsingborgs IF[†] Debrecen[†] Maribor[†] Slovan Liberec[†] Śląsk Wrocław[†] Ekranas[†] Basel[†] Celtic Dinamo Zagreb[†] Ironi Kiryat Shmona[†] Partizan[†] Sheriff Tiraspol[†] Molde[†]
AEL Limassol[†] Neftçi[†] Dynamo Kyiv Panathinaikos Copenhagen Fenerbahçe Club Brugge Vaslui Feyenoord Motherwell Maribor won 5–1 on aggregate.
Basel Anderlecht Celtic BATE Borisov Dinamo Zagreb CFR Cluj Helsingborgs IF Maribor AEL Limassol Ironi Kiryat Shmona Braga Dynamo Kyiv Panathinaikos Copenhagen Spartak Moscow Fenerbahçe Udinese Lille Málaga Borussia Mönchengladbach CFR Cluj won 3–1 on aggregate.