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system
options on the e-mini s&p 500 futures at the cme: what's the expiry date of the underlying future?
user
i don't see ewq6 in any of your links, so i can't say for certain, but when you buy an option contract on a future, the option will be for a specific future (and strike).  so the page you're looking at may be for options on e-mini s&p 500 futures in general, and when you actually purchase one through your broker, you pick a specific expiry (which will be based on the "prompt" future, meaning the next future that expires after the option) and strike. update: based on this page mirror, the option ewq7 is an option on the esu7 (sep 2017) future.  the next 3 monthly options use esz7 as the underlier, which confirms that they use the next prompt future as the underlier.
assistant