Swear It Again

UK CD1

1. "Swear It Again" (radio edit) – 4:04
2. "Forever" – 5:05
3. CD-ROM (includes filmed interview with Ronan Keating + video clips)

UK CD2

1. "Swear It Again" (radio edit) – 4:04
2. "Swear It Again" (Rokstone mix) – 4:07
3. "Ronan Keating Interviews Westlife" (audio) – 3:36

UK cassette single

1. "Swear It Again" (radio edit) – 4:04
2. "Forever" – 5:05
3. "Ronan Keating Interviews Westlife" (audio) – 3:36

European CD single

1. "Swear It Again" (radio edit) – 4:04
2. "Forever" – 5:05

US CD and cassette single

1. "Swear It Again" – 4:06
2. Snippets from Westlife

Australian CD single

1. "Swear It Again" (radio edit) – 4:04
2. "Swear It Again" (Rokstone mix) – 4:07
3. "Forever" – 5:05
4. "Ronan Keating Interviews Westlife" (audio) – 3:36
5. CD-ROM (includes filmed interview with Ronan Keating + video clips)

Australian and Japanese CD EP

1. "Swear It Again" (radio edit) – 4:04
2. "Until the End of Time" – 3:10
3. "Forever" – 5:05
4. "Everybody Knows" – 3:45
5. "Let's Make Tonight Special" – 4:52
6. "Don't Calm the Storm" – 3:46
7. "Ronan Keating Interviews Westlife" (audio) – 3:37