Royal Mail praised its delivery staff for the improved service at the beginning of this year, saying radical business changes it had made had improved its performance, and predicting more improvements.
The deliveryservice, part of the Royal Mail Group, apologised for the failure in the system which allowed people using the mail tracing service access to the name, postcode and signature at various addresses.
Some have said Saturday letter delivery could be ended if the Postal Service kept delivering packages and express mail on the weekends, as was planned.