Precise is the eighth lender to join the ASTL this year.
The ASTL is the trade body which protects and promotes the interests of short-term lenders.
Alan Cleary, managing director at Precise Mortgages, said: “We decided to join the ASTL to further promote the highest standards when dealing with customers who require short term finance.
“The ASTL’s objectives are aligned to that of Precise Mortgages’ so it was a straightforward decision for us to join and we look forward to working together in the interests of the Short Term Lending industry.”