MP Eric Illsley has admitted he fraudulently claimed more than £14,000 in parliamentary expenses.
He pleaded guilty to three false accounting charges over claims for council tax, maintenance, repairs and utility bills for his second home.
Illsley, appearing at Southwark Crown Court, previously denied all charges.
He was re-elected as Labour MP for Barnsley Central in May, but was suspended from the party after being charged and now sits as an independent.
Labour leader Ed Miliband said Illsley should now do the "right thing" and stand down.
On Friday, former Labour MP David Chaytor became the first person to be jailed over the Westminster expenses scandal.
Illsley is the only serving MP among those facing court. The judge, Mr Justice Saunders, adjourned the hearing for four weeks for a pre-sentence report.
If Illsley receives a prison term of 12 months or more he will be disqualified from being an MP under the Representation of the People Act 1981. BBC News
