Ella Toone's acrobatic effort in the 54th minute had given Marc Skinner's side a deserved lead at the Chigwell Construction Stadium, but the hosts would take a share of the spoils after Grace Fisk headed in off the post in stoppage time.
Despite the result, there was one positive for the Reds to take from the hard-fought contest, as January signing Jade Moore made her debut for the club having recovered from a serious knee injury suffered last year.
FIRST HALF
In the pouring rain at Dagenham & Redbridge's home stadium, United had a golden opportunity to take the lead inside the opening three minutes, but Toone couldn't quite connect properly with Leah Galton's low pass along the ground.