FC Halifax Town manager Neil Aspin felt his side did enough to win but this draw reduced their play-off hopes.
Lois Maynard grabbed a 90th-minute equaliser after Hamza Bencherif had given Lincoln a half-time lead.
But fifth-placed Forest Green’s win at Chester has left Halifax six points adrift of the play-off spots with four games left, although Halifax have played a game fewer.
Aspin said: “In the first half we had some good chances and didn’t take them.
“We’ve put countless throw-ins into the box so conceding from one is very disappointing.
“I was happy with the way we played in the first half, it was just the end product.
“In the second half I felt we were the team that were pushing the most and we certainly deserved getting something at the end, but we could have done with getting it earlier to give us more time to get the winner.”
Halifax fell behind when Tom Miller’s long-throw saw Bencherif head past Matt Glennon.
Jack Muldoon squandered a clear chance and Marc Roberts’s header was cleared off the line before Maynard capped a tremendous individual performance with a long-range shot that crashed into the top corner with the aid of a deflection.
Jordan Cranston was then dismissed for a second booking.
Lincoln City: Farman, Caprice, Miller, Bencherif, Cranston, Keane, Everington (Nolan 65), Wallace, Power, Tomlinson (Sam-Yorke 90), Burrow. Unused substitutes: Diagne,
FC Halifax Town: Glennon, Bolton (Jackson 60), M Roberts, Hutchison, Williams, McManus, Maynard, Pearson, Hatfield, Muldoon, Boden (Hattersley 71). Unused substitutes:Senior, K Roberts, Schofield. Referee: Dean Treleaven (Sussex).