| Status | Name | Position | Date Registered | Posts | |
|---|---|---|---|---|---|
| UnderFly | 2020-10-19 | 0 | |||
| Undergamer54 | 2021-07-08 | 0 | |||
| Underground | 2015-01-23 | 0 | |||
| underground noize | 2015-01-25 | 0 | |||
| undergroundd | 2016-07-11 | 0 | |||
| underground_bee | 2017-09-11 | 0 | |||
| underhanded-overhill | 2022-09-05 | 0 | |||
| Underknight | 2020-11-03 | 0 | |||
| underlord | 2014-01-24 | 0 | |||
| underlust frisk | 2023-03-16 | 0 | |||
| UnderMath | 2018-07-24 | 0 | |||
| UnderPowered | 2020-04-09 | 0 | |||
| Underscore | 2013-07-07 | 0 | |||
| Undershot | 2012-09-29 | 0 | |||
| underspark | 2022-08-08 | 0 | |||
| Understuck | 2016-08-04 | 0 | |||
| undertaken | 2022-05-16 | 0 | |||
| Undertaker | 2014-04-19 | 0 | |||
| Undertaker_Fan | 2018-04-26 | 0 | |||
| Undertale | 2016-03-26 | 0 | |||
| Undertale | 2016-03-26 | 0 | |||
| UNDERTALE FRISK | 2018-03-24 | 0 | |||
| Undertale.trash | 2016-01-16 | 0 | |||
| Undertale1 | 2020-12-27 | 0 | |||
| Undertale123 | 2017-12-30 | 0 | |||
| Undertale26 | 2016-12-18 | 0 | |||
| UndertaleGamingWithFrisk | 2018-02-18 | 0 | |||
| Undertalegirl1002 | 2016-11-19 | 0 | |||
| UndertaleLover01 | 2016-07-16 | 0 | |||
| UndertaleRed | 2017-10-20 | 0 | |||