| Ultimate Masters (254 items) | UMA | 2018-12-07 |
| Ultimate Masters Tokens (16 items) | TUMA | 2018-12-07 |
| Unfinity (638 items) | UNF | 2022-10-07 |
| Unfinity Sticker Sheets (48 items) | SUNF | 2022-10-07 |
| Unfinity Tokens (14 items) | TUNF | 2022-10-07 |
| Unglued (88 items) | UGL | 1998-08-11 |
| Unglued Tokens (6 items) | TUGL | 1998-08-11 |
| Unhinged (168 items) | UNH | 2004-11-19 |
| Unhinged Promos (1 items) | PUNH | 2004-11-19 |
| Universes Within (30 items) | SLX | 2022-03-03 |
| Unknown Event (512 items) | UNK | 2023-02-15 |
| Unlimited Edition (302 items) | 2ED | 1993-12-01 |
| Unsanctioned (96 items) | UND | 2020-02-29 |
| Unsanctioned Tokens (6 items) | TUND | 2020-02-29 |
| Unstable (268 items) | UST | 2017-12-08 |
| Unstable Promos (1 items) | PUST | 2017-12-08 |
| Unstable Tokens (20 items) | TUST | 2017-12-08 |
| URL/Convention Promos (18 items) | PURL | 2009-02-08 |
| Urza's Destiny (143 items) | UDS | 1999-06-07 |
| Urza's Destiny Promos (1 items) | PUDS | 1999-06-07 |
| Urza's Legacy (143 items) | ULG | 1999-02-15 |
| Urza's Legacy Promos (2 items) | PULG | 1999-02-15 |
| Urza's Saga (357 items) | USG | 1998-10-12 |
| Urza's Saga Promos (1 items) | PUSG | 1998-10-12 |
| Vanguard Series (32 items) | PVAN | 1997-05-01 |
| Vintage Championship (35 items) | OVNT | 2003-01-01 |
| Visions (167 items) | VIS | 1997-02-03 |
| War of the Spark (311 items) | WAR | 2019-05-03 |
| War of the Spark Promos (176 items) | PWAR | 2019-05-03 |
| War of the Spark Tokens (19 items) | TWAR | 2019-05-03 |
| Warhammer 40,000 Commander (617 items) | 40K | 2022-10-07 |
| Warhammer 40,000 Tokens (31 items) | T40K | 2022-10-07 |
| Weatherlight (167 items) | WTH | 1997-06-09 |
| Welcome Deck 2016 (16 items) | W16 | 2016-04-08 |
| Welcome Deck 2017 (30 items) | W17 | 2017-04-15 |
| Wilds of Eldraine (381 items) | WOE | 2023-09-08 |
| Wilds of Eldraine Art Series (81 items) | AWOE | 2023-09-08 |
| Wilds of Eldraine Commander (173 items) | WOC | 2023-09-08 |
| Wilds of Eldraine Commander Tokens (10 items) | TWOC | 2023-09-08 |
| Wilds of Eldraine Promos (160 items) | PWOE | 2023-09-08 |
| Wilds of Eldraine Tokens (18 items) | TWOE | 2023-09-08 |
| Wilds of Eldraine: Enchanting Tales (103 items) | WOT | 2023-09-08 |
| Wizards of the Coast Online Store (1 items) | PWOS | 1999-09-04 |
| Wizards Play Network 2011 (3 items) | PW11 | 2011-01-01 |
| Wizards Play Network 2012 (3 items) | PW12 | 2012-01-01 |
| Wizards Play Network 2021 (6 items) | PW21 | 2021-06-18 |
| Wizards Play Network 2022 (6 items) | PW22 | 2022-03-05 |
| Wizards Play Network 2023 (11 items) | PW23 | 2023-01-01 |
| Wizards Play Network 2024 (18 items) | PW24 | 2024-01-01 |
| Wizards Play Network 2025 (16 items) | PW25 | 2025-01-01 |