The first regulated period under the Transparency of Lobbying, Non-party Campaigning and Trade Union Administration Act 2014 starts on 19 September, the day after the Scottish independence referendum, and lasts until the general election on 7 May 2015.
The act, which received royal assent in January, lowered the maximum amount non-party campaigners can spend on certain regulated campaigning activities and introduced a campaign spending limit of £9,750 per parliamentary constituency.
It also increased the amount campaigners may spend before being required to register with the Electoral Commission, and substantially widened the range of regulated activities, expenditure on which counts towards that total.
The commission has produced 16 guidance documents plus further fact sheets on how to comply with the rules. In addition, it will run webinars over the summer to help explain the new rules and will continue to send out email updates for campaigners, allowing it to respond to any new issues raised.
Among those 16 documents is the sector-specific Charities and Campaigning guide, but other documents are also relevant to charities.
Elizabeth Chamberlain, policy manager at the National Council for Voluntary Organisations, said: "Charities that campaign will have to read all the documents to have a good understanding of the issues as a whole."
Chamberlain said the guidance gave clarity on some areas, such as what charities could say in their election manifestos, and reassured charities that if a policy they supported was later adopted by politicians or their parties it was not necessarily then viewed as party political activity.
"If it has not provided complete clarity, the Electoral Commission has at least identified key issues," she said. Greater clarity was needed on some issues, she said, including joint campaigns and the constituency spending limit.
Rosamund McCarthy, a partner at the law firm Bates Wells Braithwaite, said that constituency spend was a potentially difficult area. "This is an area on which the Electoral Commission could be open to challenge," she said. Applying the guidance definition of a charity's "committed supporters" could also prove tricky, she said.
"When the bill was going through parliament, ministers were very clear that the law was not meant to restrict the normal policy campaigning activity of charities," said McCarthy. But she said that the law as it stood could do just that in some cases.
McCarthy and Chamberlain both expressed disappointment that the guidance was released so late. The Electoral Commission had promised it would be available in early July, but its release yesterday leaves charities just over two months to prepare for the new rules at a time when many charities might be going through a summer lull.
"This might be the last week in which many boards will be meeting before September, so this creates real governance issues," McCarthy said.
Paula Sussex, chief executive of the Charity Commission, said campaigning was a serious matter for charities. "All charities thinking about engaging in campaigning activity in the run-up to the next election need to follow the Electoral Commission’s guidance, as well as the commission’s own guidance on campaigning and political activity," she said. "I urge all charities that might be campaigning or involved in political activity in the months ahead to make sure they understand what is required of them."
The commission's existing guidance, Speaking Out: Guidance on Campaigning and Political Activity by Charities, remains in force.