What is the suffix for economy?

There isn't a single, universally accepted suffix specifically for "economy." However, depending on the context, various suffixes can be used to create related terms, like:

-ic: Economic (adjective)

-ist: Economist (noun)

-ics: Economics (noun)

-ical: Economical (adjective)

-ization: Economization (noun)

-ize: Economize (verb)

The specific suffix you use will depend on the meaning you want to convey.