Charities can use social media to campaign on political issues but they must be aware of the risks this can cause to their reputation, a watchdog has stated.

The Charity Commission has published new guidance for organisations on how to use social media effectively.

The commission’s director of communications and policy, Paul Latham, said the guidance would “help charities to navigate their use of social media with greater confidence”.

It follows a formal consultation, which ran in the first three months of the year, and will “support the commission to regulate this high profile and fast paced area in a fair and balanced way”, he added.

The guidance comes just a few weeks after the Royal Society for the Protection of Birds (RSPB) issued an apology over a social media post accusing the Government of lying about environmental commitments.

The conservation charity lashed out on X, formerly known as Twitter, at plans to scrap water pollution restrictions for housing developments in England.

RSPB chief executive Beccy Speight said she did not approve the post and it did not go through “normal protocols”, as she declared the charity was “not entering politics”.

The commission has now confirmed it is investigating the “serious mistake”, although it has not launched an inquiry.

A Charity Commission spokesperson said: “The trustees have shared information on the steps they are taking to review how the incident happened, and to ensure such mistakes do not occur in future.

“We have opened a regulatory compliance case to fully assess this information and to determine our next steps.”

Meanwhile, Home Secretary Suella Braverman has previously accused some charities of “actively undermining efforts to curb illegal migration”, describing them as being “comprised of politically motivated activists masquerading as ‘humanitarians’”.

But the general social media guidance issued by the commission on Monday stated clearly that “charities can use social media to engage in campaigning and political activity”, so long as they abide by the additional rules already in place.

These include that the political activity “supports their purpose and is in their best interests”, and that charities must remain independent and not give their support to a political party.

However, trustees, charity employees and other individuals “have the right to exercise their freedom of expression within the law”, the guidance states, including “personally supporting a particular political party or (during an election) a particular candidate, something a charity cannot do”.

Charity Commission chairman, Orlando Fraser, told the Guardian: “I will robustly defend charities’ right to campaign lawfully, even where such campaigning covers sensitive or politically divisive ground.”

Mr Latham said in a statement accompanying the latest guidance: “There are many benefits to using social media, which can be an effective tool for campaigning, communicating with the public and reaching new and existing supporters.

“However, trustees need to be alive to the risks it can generate, including to a charity’s reputation.

“We have published this guidance because we want trustees to think carefully about what they want to achieve when using social media and then apply our guidance to help ensure their charity is protected.”

He added said trustees have a “duty” to “act responsibly, in their charity’s best interests, and in line with the law”.

The commission’s guidance advises charities that if they are planning campaigning or political activity on social media, they should ensure everyone involved knows the rules and that they take extra care around elections.