Yes, a charity can lobby, within limits it can measure

Many nonprofit leaders believe charities cannot lobby at all. That is not the law. A 501(c)(3) public charity may lobby, which means trying to influence legislation, as long as lobbying is not a substantial part of its activities. What it may never do is support or oppose candidates for office.

The difficulty is that "substantial" is not defined. To replace that uncertainty with a number, most public charities can make what is called the 501(h) election by filing Form 5768 with the IRS. An electing charity is instead subject to an expenditure test, a sliding scale based on the size of its budget, with an overall cap on lobbying spending.

The expenditure test counts only money spent, so volunteer time that costs the organization nothing generally does not count. It also defines what counts as lobbying, which makes planning easier. Churches and private foundations cannot make the election.

Organizations that expect to do any lobbying should talk with an adviser about whether to elect, and should track lobbying expenses from the start either way. They are reported on Schedule C of Form 990.