Report on a magnetometry survey, conducted to inform the conservation and management of the field known as the Tiltyard, to the south-east of Tattershall Castle. The results of the survey accorded well with previous geophysical investigations of the same area conducted in 1997 and 2009, and recorded a number of magnetic anomalies, thought to represent a range of pit and ditch-like features across the site. The survey again identified a linear series of magnetic anomalies in the western half of the field, which had previously been thought to represent the remains of ridge and furrow or a possible former course of the outer moat. An explanation of these anomalies as being the remains of ridge and furrow was thought to be more likely, given their morphology.