The list includes all R18s from the first hardcore R18 of 16th August 2000 through 2003.
Thereafter only cuts of significant interest have been included
Thanks to Sergio who now maintains the complete list of R18s on his site 

Hardcore R18s Cuts Latest 0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

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Japanese adult film (Phoenix Films)
Submitted in 2008, running time 122:34s
Cut by 4:04s. Compulsory cuts were required to remove images of urination during sexual activity

by Freddie Morse;
Karla Romano, Charlie Holays, Renee Richards, Sahara Knite, Jamie Brooks, Suzie Best, Zoe, Sonsi, Tony James, Danny Boy, Ben, Chuck Loads, Dougie, David Charles.
120m 7s. Cuts of 0m 16s were required. The cuts were Compulsory.
Cut required to remove abusive activity (gagging during aggressive deep throat fellatio) from a sex work

by Dries Breyne
Not known
53m 54s. Cuts of 5m 40s were required. The cuts were Compulsory. A cut was required to a scene of intercourse and ejaculation in which one participant repeatedly acts as if she is not consenting to the activity.

by Not known
Not known
117m 40s. Cuts of 1m 24s were required to remove potentially harmful and abusive elements from graphic sequences of sexual activity.

by Dries Breyne
Not known.
68m 57s. Cuts of 2m 25s were required. The cuts were Compulsory. Compulsory cuts were required to remove sight of potentially harmful sexual activity (in this case, a woman's vagina being penetrated by the handle of a feather duster)

(Black Chip)
Submitted in 2007, running time 80:26s
Cut by 2:06s Cut required to sight of fisting

Czech adult video (Sweet Pictures)
Submitted in 2009, running time 85:19s
Cut by 8:11s. Five cuts were required for sexual activity involving actual or potential harm (in this case anal penetration with small mobile phones)

by Patrick Collins (Black Chip)
With Alicia Rhodes, Cherry Poppins, Giana, Kinzie Kinner, Cierra Sage, Lane Oi, Alex Devine, Luccia, Persia, Tiana Lynne, Dick Nasty, Roscoe Bowltree, Rod Fontana.
Submitted in 2009, running time 105:10s
Cut by 14:08s. Compulsory cuts required to remove sight of urolagnia (urination accompanied by sexual activity). Compulsory cuts also required to remove potentially harmful sight of gagging or choking during deep throat fellatio.

by Paul Sky (Playhouse)
With Eva, Anna D, Alena, Hana, Anna A, Jana, Lucky Smile, Marcel, Martin Schneider.
Submitted in 2010, running time 191:03s
Cut by 16s. Cut was required to remove sight of urination during vaginal penetration

by Paul Sky (Scala)
With Helga, Ivana Pinky.
Submitted in 2009, running time 190:33s
Cut by 1:39s. Cuts were required to scenes of urination during vaginal penetration and vaginal fisting

by Jack Remy
Summel Rose, Bunny Blue.
81m 9s. Cuts of 0m 23s were required., some or all of these cuts were substitutions. The cuts were Compulsory.
Cut required to the title to remove a phrase suggestive of underage participation in this sex tape. A second cut required to remove reference to an 18 year old baby-sitter having wanted to have sex with her former employer for eight years. Cuts made

Not known
Not known.
194m 10s. Cuts of 1m 35s were required. The cuts were Compulsory. Cuts required to remove advertisements featuring youthful women for whom assurances that they are over 18 cannot be provided.

Not known
Kat Kleevage, Sindy Cummings, Austin O'Riley, Jenny Loveitt, Sammy Sparks
77m 22s. Cuts of 0m 11s were required., some or all of these cuts were substitutions. The cuts were Compulsory. Cut required to the title to remove a phrase suggestive of underage participation in this sex tape

by Omar Williams
Maria,Layla~Jade,Debbie
109m 15s. Cuts of 3m 57s were required to remove all sight of activity likely to outrage public decency (real sexual activity in a car in a public UK location). Cuts made in accordance with law on indecent exposure.

by Disanti (Playhouse)
With Ariana Kaye, Natasha Roman.
Submitted in 2009, running time 162:52s
Cut by 1:07s Cuts are required to remove potentially harmful and abusive behaviour (in this case apparent forced fellatio causing repeated gagging)

by Robbie Fischer
Bobbi Eden, Cathy Oz, Christie, Dani Woodward, Sassy, Tracie Kelly, Ben English, Brett Rockman.
139m 23s. Cuts of 1m 30s were required. The cuts were Compulsory. Distributor was required to remove two underage sex references and abusive sex scenario

adult video by Stephen English (Mebray)
Submitted in 2007, running time 54:24s
Cut by 8:38s The cuts were made to the sight of injury that went beyond the legal test of trifling and transient

1975 US adult film by Radley Metzger (Henri Paris)
With Constance Money, Jamie Gillis, Jacqueline Beaudant, Terri Hall, Ras Kean, Gloria Leonard, Calvin Culver, Mary Stuart, Janet Baldwin, Cynthia Gardner, Helene Simone, Marlene Parker.

Submitted in 2005 by Arrow, running time 84:39s
Passed R18 uncut

Previously the BBFC cut 1:55s from the softcore 1983 cinema release

Before that the BBFC rejected the 1977 cinema release.

See review from IMDb: Simply a great film

Radley Metzger has created an unbelievable amalgamation of great script, fantastic actors, and the best production value I've ever seen. Other films may have spent more on cheesy helicopter shots or period costumes, but you will never find a porn movie as good as this. The opening of Misty Beethoven holds up not only under the porn standard, but under any film standards. Simply a great film.

adult video by Don Sigfredo (Sweet Pictures)
Submitted in 2008, running time 86:19s
Cut by 8:12s Cuts were required to remove multiple instances of abusive humiliating behaviour and choking, retching and aggressive handling of the head during oral penetration with multiple objects

by Mike John
Aurora Snow,Diamond,Fawna
139m 28s. Cuts of 5m 19s were required to verbal references to underage sex and sexual scenes of an abusive and degrading nature (repeated gagging during 'deep throat' fellatio)

by Chico Wang; Khan
Roxy Jezel, Bella Maria, Ariana, Elizabeth.
133m 49s. Cuts of 5m 53s were required., some or all of these cuts were substitutions. The cuts were Compulsory. Distributor was required to make cuts to remove verbal references to underage sex and incestuous relationships, verbal references to choking and sight of male performer choking female performer

by Tanya Hyde; Steven Angelo; Gazzman (Harmony Films)
Submitted in 2007, running time 234:29s
Cut by 12:13s: Cuts required to remove potentially harmful and abusive sexual activity and dialogue (gagging and sustained semi-gagging and gurgling during fellatio, and reference during fellatio to wanting to choke on man's penis).

by Not known
Not known
77m 53s. Cuts of 0m 35s were required to sight of urolagnia (in this case a woman urinating during masturbation and dildo penetration, and a woman's bare breasts being wetted with urine),  

Hardcore R18s Cuts Latest 0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z