1. Tony Iommi - 1969 to Present

NOTES

• Tony Iommi briefly quit Sabbath and played with Jethro Tull for a couple of weeks in 1969 before Sabbath recorded their first album.
• Brian May of Queen played a guest guitar solo on the track "When Death Calls" on 1989's The Headless Cross. 

1. Ozzy Osbourne - 1969 thru September 1977
2. Dave Walker - October 1977 thru January 1978
3. Ozzy Osbourne - January 1978 thru May 1979
4. Ronnie James Dio - May 1979 thru November 1982
5. Ian Gillan - January 1983 thru March 1984
6. Dave Donato - Unknown in 1984 for a few weeks
7. Jeff Fenholt? - January 1985 to September 1985
8. Glenn Hughes - September 1985 thru March 1986
9. Ray Gillen - March 1986 thru August 1987
10. Tony Martin - August 1987 thru April 1991
11. Ronnie James Dio - April 1991 thru November 13, 1992
12. Rob Halford - November 14 & 15, 1992
13. Tony Martin - Spring 1993 to December 1995 (Band Inactive from Jan 96 to March 97)
14. Ozzy Osbourne - March 1997 to Aug 25, 2004
15. Rob Halford - August 26, 2004 (only one gig, stood in when Ozzy was sick)
16. Ozzy Osbourne - August 27, 2004 to present

NOTES

• Bill Ward sang lead vocals on It's Alright from Technical Ecstasy and Swinging the Chain from Never Say Die.
• Dave Walker never recorded, but an alternate version of Junior's Eyes exists with him.
• Dave Donato was officially a member, but never recorded or played live.
• Jeff Fenholt's position in the band is in dispute. I'm trying to straighten this out, but the Fenholt camp says they have pictures of him with the band and that Fenholt's uncredited for songwriting on Seventh Star. The Sabbath camp says he only "tried out" for the part.
• Ray Gillen replaced Glenn Hughes about 10 dates into the Seventh Star tour, then recorded The Eternal Idol, and left before it was released.
• The only surviving part of Ray's voice on the released Eternal Idol album is some laughing on the track "Nightmare". 
• Rob Halford sang for Sabbath in Nov 92 when Dio refused to open for Ozzy. 
• Ice-T of the band Body Count did a guest vocal on the song The Illusion of Power from 1995's Forbidden.  

1. Geezer Butler - 1969 through mid 1984
2. Gordon Copley - January 1985 thru September 1985
3. Dave Spitz - September 1985 thru September 1986
4. Bob Daisley - September 1986 through October 1986
5. Dave Spitz - July 1987
6. Joe Burt - November 1987 thru December 1987
7. Geoff Nicholls - May 1988
8. Laurence Cottle - October 1988
9. Neil Murray - April 1989 thru April 1991
10. Geezer Butler - April 1991 thru October 1994
11. Neil Murray - October 1994 thru December 1995
12. Geezer Butler - Mar 1997 to current

(Yes, I realize there are points where there are no defined bassist.  See the timeline page for further details).

NOTES

• Depending on whom you talk to, Geezer officially left and came back during the pre-production for Heaven & Hell, both Craig Gruber and Geoff Nicholls was originally brought in to play bass during said time.
• There was a (largely unfounded) rumour that Craig Gruber actually played the bass on Heaven & Hell, and not Geezer.
• Gordon Copley plays bass on the track No Stranger To Love from 1986's The Seventh Star. Gordon Copley was the bassist for Lita Ford's band in early 1985, and when she went back out on tour, Gordon went with her, leaving Sabbath.
• Bob Daisley was brought in to finish the bass tracks on Eternal Idol after Dave Spitz left during production of the album.
• Joe Burt played only on the Eternal Idol Tour.
• Laurence Cottle played on the Headless Cross album only.
• Geoff Nicholls did play bass during a one off charity gig in the UK on May 29, 1988.

1. Bill Ward - 1969 thru August 1980
2. Vinny Appice - August 1980 thru November 1982
3. Bill Ward - January 1983 thru August 1983
4. Bev Bevan - August 1983 thru Summer 1984
5. Bill Ward - Summer 1984
6. Eric Singer - September 1985 thru January 1987
7. Bev Bevan - June 1987 to October 1987
8. Terry Chimes - November 1987 thru March 1988
9. Cozy Powell - October 1988 thru April 1991
10. Vinny Appice - April 1991 thru November 16, 1992
11. Bobby Rondinelli - Spring 1993 thru August 1994
12. Bill Ward - August 1994 through September 1994
13. Cozy Powell - October 1994 thru July 1995
14. Bobby Rondinelli - July 1995 thru December 1995
15. Mike Bordin - Mar 1997 to June 29, 1997
16. Shannon Larkin - July 1, 1997 (one gig only - stood in when Mike Bordin couldn't make the gig)
17. Bill Ward - November 1997 May 1998
18. Vinny Appice - May 1998 to September 1998 (also was on tour during Jan/Feb 1999 as a backup, but did not play)
19. Bill Ward - September 1998 to present

(Yes, I realize there are points where there are no defined drummer.  See the timeline page for further details).

NOTES

• Bill Ward only recorded for Born Again, he never toured.
• Bill Ward was officially part of the band after the Born Again tour when Dave Donato was around.
• Bev Bevan is credited with percussion on The Eternal Idol.
• Terry Chimes only played during the Eternal Idol tour. He does appear in the video for The Shining.
• Bill Ward played with Sabbath for 3 dates in South America in 1994.
• Cozy Powell left after the US leg of the Forbidden Tour, claiming exhaustion. It was an amiacable split. 
• In early June of 2004, it was announced that Mike Bordin would play Ozzfest 2004.  That never actually happened, and Bill Ward played.

1. Rick Wakeman - 1973
2. Jezz Woodruffe - ??? thru 1977
3. Don Airey - 1978
4. Geoff Nicholls - 1979 thru ??, 2004
5. Adam Wakeman - June 2004 to present

NOTES

• Tony Iommi reportedly played keyboards on Volume 4.
• Rick Wakeman played on the Sabbath, Bloody Sabbath album.
• Jeff Woodruffe played on the Technical Ecstasy album and tour.
• Don Airey played on the Never Say Die album and tour.
• The keyboard duties before 1976 are sketchy. Beyond what's listed above, it's not generally known who did it.
• Geoff Nicholls was originally brought in to play bass in 1979, but moved to keyboards and has been there ever since.
• Geoff did play bass live for the band once - May 29, 1988.