On 24 May 2017, Daniels joined Championship club Brentford on a free transfer and signed a three-year contract, with an option for a further year. Daniels appeared in each of the club's four cup matches during the 2017–18 season and made his league debut versus Hull City on the final day, in which he helped preserve a 1–1 draw by saving a second-half penalty. Aside from cup appearances and two league starts, Daniels was again backup to Daniel Bentley for the majority of the 2018–19 season, until a season-ending shoulder injury suffered by Bentley in March 2019 allowed Daniels a run in the team in league matches and he finished the season with 19 appearances in all competitions.