The Office of Fair Trading (OFT) has delayed the approval and launch of compulsory ombudsman services for estate agents.
The move followed a two-year OFT probe into the estate agents industry
Under new laws, estate agents have to join an ombudsman scheme, which will hear complaints from unhappy customers.
The scheme was due to start on 6 April and four ombudsman services had applied for endorsement from the OFT.
But the OFT said it is still ironing out issues with the applicants and the start date has been postponed.
Under the Consumers, Estate Agents and Redress Act of 2007, an estate agent can be prevented from operating if it is not attached to an OFT-approved ombudsman service that can resolve disputes and offer compensation.
The act was prompted by a desire to give people more protection from estate agents. Until now, the £185bn-a-year industry has been self regulated.
Only about 60% of estate agents were members of ombudsman schemes at the end of 2006. A disproportionate number of complaints about estate agents are about firms not in these schemes.
Complaints about estate agents include inaccurate description of properties or delays in passing on offers to sellers.
Four schemes have applied for OFT endorsement. They are the Ombudsman for Estate Agents, The Surveyors Ombudsman Service Limited, IDRS Ltd, and The Register of Estate Agents.
The clause in the 2007 Act making membership of a scheme compulsory for all estate agents will only be active once approval is given.
Mark McLaren, spokesman for consumer group Which?, said: "We have been waiting four or five years for this. We do not know what the reason for the delay is but we hope any delay will be very short.
"We strongly support all estate agents being members of complaints schemes."