An MLS (Board of Realtors, or Association of Realtors) may require vendors like Showcase IDX to pay Data Access Fees. These fees can be billed to vendors monthly, quarterly or annually. To cover the cost, Showcase IDX charges an "MLS Pass-Thru Fee" (aka Data Management Fee) that gets passed through to customers who use those feeds. These fees vary from $5/month up to $30/month.
Some MLSs don't charge a vendor any fee at all. In these cases, we would not charge a fee to the customer either.
You can check if your MLS has a pass-thru fee on their information page by visiting https://showcaseidx.com/mls-coverage/.
Although the rates may vary slightly, 99% of IDX companies charge these fees.