Why don't I see my filter in the marketing campaign setup?

I can't see the filter I want to use for my new marketing campaign

You can create different filters for your prospects, leads, and deals. And these filters will only appear for that specific type of opportunity. When you create a new marketing campaign, one of the first options you'll select is the Campaign Stage.

What you select here will determine which filters are available for the campaign. For example, if you select Prospects as the campaign stage, you'll only see the filters you've created for your prospects.