A woman who stopped using the services of a children's party entertainer after learning she publicly supported the No side of the same-sex marriage debate has been cleared by the Fair Work Ombudsman.

Madlin Sims's party business ended its relationship with a contractor, identified only as Madeline, after she posted a Facebook frame saying "it's OK to vote No".

At the time Ms Sims said "I don't like shit morals", in a Facebook post about her decision.

The case was subsequently referred to Fair Work to determine whether Ms Sims broke the law by firing Madeline and whether Ms Sims should have treated her as an employee rather than a contractor.

But in a letter a fair work inspector said that due to insufficient evidence to determine whether the woman met the definition of employee, the Fair Work Ombudsman (FWO) would pursue no further action.

"The investigation … has not identified any contravention of the Commonwealth workplace laws or the relevant industrial instrument," the letter said.

"Discrimination occurs in the workplace when an employer takes adverse action against an employee because of a protected attribute.

"As the FWO has been unable to determine the nature of the engagement based on the evidence available, we will be taking no further action in relation to this matter at this time."

The inspector noted there was some evidence that the relationship did indicate employment, while other evidence indicated a contracting situation.

Ms Sims said the decision was a "massive weight off her shoulders," and said while she had few regrets, she hoped she had not damaged the Yes campaign's brand.

"I would definitely do it again," she said.

"That business is like my little second baby, my pride and joy … I was very scared of losing that.

"The biggest relief for me was when the Yes vote was finally passed.

"Having this pop up after that happened, it's been a stressful few months."