SingTel SMS services have been restored, said the telco on Tuesday afternoon in an update on its Facebook page.
"However, some applications which use SMS may take a little longer to come back on line," it said. "We are continuing to monitor services closely and apologise for the inconvenience caused."
In an earlier post on the same day, SingTel notified customers of intermittent difficulties in sending and receiving SMS messages. The telco had said that it would provide regular updates as its engineers investigate the issue and work to restore the service as quickly as possible.
SingTel subscriber Tian Xian Jun, 29, who works in a bank, said: "I couldn't log into internet banking just now at about 2.15pm as I couldn't receive the one-time password and I didn't have my token."