The service, which is trying to register as a charity, explains in its annual report that it expects the Charity Commission to object to the content.
"The commission might insist that our occasional blog-based reprimands of poorly performing charities are not charitable activities," the report reads.
A spokeswoman for the Charity Commission said that charities needed to consider whether their blogs directly furthered their charitable purposes or supported their work in indirect ways.
"When we are considering if an organisation is a charity, understanding why a blog or other activity is carried out helps us to ascertain the purpose of the organisation and whether this purpose is charitable," she said.
Both Shelter and Acevo, whose chief executives Adam Sampson and Stephen Bubb are regular bloggers, told Third Sector they did not consult the commission before starting their blogs.