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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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)

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 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

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 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