Tax code changes continue to puzzle a significant number of donors when it comes to their charitable giving, according to new research from Marts & Lundy, a fundraising consulting firm.

“Overall, we are finding that regardless of their giving status — major gifts or annual fund — donors are uncertain about what tax changes will mean to their giving,” Marts & Lundy’s chief executive, Philippe Hills, said in a statement.

Hills recently cited a report that predicted that giving over the next two years would grow even in the wake of changes to the tax code.

For the new study, Marts & Lundy interviewed 105 top donors, and conducted online surveys that elicited 2,542 responses from donors at all income levels to its nonprofit clients.

In the interviews, 53% of donors said their giving would remain unchanged, while 37% were uncertain. Ten percent said they would increase their giving.

Online responses showed a different picture: 45% of donors with different income levels said they were unsure, while 39% said their giving would stay the same. And in contrast to the interviewees, 6% said they would reduce their giving.

The research found variance in responses across giving levels.

Forty-four percent of respondents who reported annual donations of less than $5,000 said they were unsure how the new tax law would affect their giving, compared with 31% of those who give more than $5,000 annually and 37% of top donors.

More than half of both interviewees and donors of $5,000 or more said their giving would remain the same, compared with 38% of smaller donors.

Interestingly, donors in the latter group were likelier to say they would increase their giving: 14%, compared with 11% for big donors and 10% for interviewees.

— Check out Charitable Giving by Taxpayers Who Don’t Itemize Plunges on ThinkAdvisor.