Only two points separated fourth-placed Horncastle from Louth, in fifth, at kick-off, and the hosts went ahead after 19 minutes through Jonathan Timmins.
Horncastle would go on to lead three times, only to be pegged back on each occasion, Joe Marshall, Frazer Chapman and Bradley Coulam netting for the White Wolves.
Louth’s battling qualities shone through, snatching a point even after Chapman was sent off for a second yellow card.
Next up for Louth, who stayed fifth, is a home match with Brigg Town CIC Reserves on Saturday.
Kick-off at Saltfleetby is 3pm.