Sam Younger, the commission's chief executive, says some trustees are too relaxed about their legal duty to get their financial documents to the regulator.
The Charity Commission will be tougher on charities that fail to file accounts on time, according to Sam Younger, its chief executive.
In a commentary published this morning on the regulator's website, Younger says research carried out by the commission among charities that filed their accounts late "bolstered the case for introducing penalties for charities that are late in filing their accounts with us".
Younger will tell the commission's annual public meeting in London today that some trustees are "too relaxed about their legal duties" when it comes to filing annual returns and that the regulator needs to "toughen up its message" on late filing.
Figures gathered from 400 late-filing charity accounts from 2011, released today by the commission, show that more than a third were signed off before their filing date, but had not been passed to the regulator on time.
The commission also found that, out of the 400, nearly a quarter of charities with incomes of more than £250,000 filed late accounts in each of the previous five financial years.
In his article on the commission's website, Younger says the findings, which include figures showing that almost four out of 10 late-filing charities were able to file their accounts with Companies House on time, "tell of a curious lack of urgency towards meeting the requirements of charity law and complying with the principle of accountability".
He says any penalty regime, such as Lord Hodgson's suggestion in his review of the Charities Act 2006 that late-filing charities should be unable to collect Gift Aid, would take time to implement and require legislative change.
"But charities should take note that the 'benefit of doubt' balance is shifting," says Younger. "In the past, we were more cautious about discussions around penalties, as any fine a charity pays detracts from the sum it can put towards furthering its charitable aim.