Councils are lagging behind in co-operating with rules designed to lift the veil on local government spending, an investigation of more than 150 authorities has found.
Some town hall bosses are waiting several months to publish data on everyday services and big ticket purchases despite it being a cornerstone of Government plans to increase transparency and accountability at local level.
Most data is reproduced on council websites within two months of the purchase, though others are leaving it much longer. One authority has outright refused to publish the figures on its website.
Local Government Minister Brandon Lewis said: "Greater power for local government must go hand in hand with greater local transparency and accountability, and local taxpayers have a right to see where their council's cash is going.
"We expect all local authorities to publish spending information without exception - it is unacceptable for councils to hide this data from local people."
Transparency measures were originally announced in 2010 for councils to publish details of spends over £500.
Some councils later adapted this to cover purchases over £250, with data typically including spends on equipment and service hire.
But last year Local Government Secretary Eric Pickles announced plans to make the discretionary measures bound by statute.
Depending on the parliamentary process, publication of £500 spends should become mandatory by the spring. The transparency code says council spending data should be published not later than one month after the quarter to which the data and information is applicable.
Mr Lewis said: "That's why we are now making our transparency code compulsory for all councils, meaning that they must publish their spending information over £500 every quarter.
"This new wave of town hall transparency will give armchair auditors the power to expose municipal waste - from surplus offices and corporate credit cards to trade union pilgrims, and help councillors drive down costs."
According to an examination of 152 council transparency pages on January 2 this year, the majority (67) had included figures up to and including November's accounts, while an additional 50 councils had updated as far as October, and a further 17 to September.
It meant data for around one in 10 councils was at least four full months behind.
The Royal Borough of Kensington and Chelsea and fellow London borough Lambeth had not updated since March 2013, according to council transparency pages accessed through the Government's Directgov database.
Wigan Metropolitan Borough has decided not to upload any data since a website relaunch a year ago.
A council spokesman said: "Previously we did publish the information on our website, though we found it wasn't very helpful.
"People would often contact us to specify on particular elements. Therefore we decided to provide the information to those who requested it - that way we are able to tailor information according to what they wanted - making it more accessible and thereby complying by the transparency rules."
However, the spokesman confirmed there was no mention of this service on the council website, and added: "If a member of the public, for whatever reasons, wanted the information they would ask."