As of July 29, Scopus will include an open access indicator for indexed journals.
Here's an excerpt from the announcement:
Out of the +21,000 active journals indexed in Scopus, 3,785 are currently (June 2015) registered as Open Access (OA) journals. . . .
In Scopus, journals are registered as being OA journals only if they are registered as Gold OA or Subsidized OA at one or both of the following sources: Directory of Open Access Journals (DOAJ) and the Directory of Open Access Scholarly Resources (ROAD).