The breach started back in May but wasn't discovered until late July.
Equifax is allowing consumers to check if their information was breached by providing their name and the last 6 digits of their social security number. Regardless of whether it was impacted or not, Equifax is providing an option for consumers to enroll in the TrustedID Premier program. The enrollment period runs through November 21, 2017. You can access the enrollment site here:
Read Equifax statement here: https://www.equifaxsecurity2017.com/potential-impact/