A method that has shown to increase customer survey response rates is to choose optimal times to send out surveys, according to ZenDesk. For instance, sending surveys after peak business hours between 6 p.m. and 4 a.m. ensures that they are seen first thing the next morning.
Surveys sent out during busy daytime hours are more likely to get lost in the shuffle of other emails. Other tactics that improve responses include creating shorter surveys with personal touches, such as the customer's name, and making the content highly targeted to personal interests and needs. Offering to give away something for free or a special discount also works.