Thomas told delegates at the e-Crime Congress in London that there is a thriving economy in stolen information, and that he could tell anyone in the room what it would cost to get their health details, bank account statements or credit card numbers.
Sensitive information is being bought by private investigators, criminals, journalists and even local councils, according to Thomas. But when cases are brought to court the offenders rarely get serious sentences.
"The results have been disappointing," he said. "Either a derisory fine or a conditional discharge. Nothing makes an Information Commissioner more mad than a conditional discharge."
The call was backed up by Conservative shadow home affairs minister James Brokenshire who said that tougher sentences are needed to deter criminals from offending.
"If the law is to be meaningful it needs tough sentencing," he said. "The law is ineffective if the criminal thinks he will receive either a small sentence or none at all. That is what is happening at the moment."
In January News of the World royal editor Clive Goodman was sentenced to four months in prison for intercepting mobile phone messages, but served only a month in jail before being paroled.