You can deploy a customer survey as soon as the customer finishes their first transaction with you. A quick follow-up asking about their experience with your order process is fine, as long as it doesn’t exceed a few survey questions.
You can follow up with a more extensive customer survey once the customer has received your product and had an opportunity to use it. At this point, you can ask more questions in the survey, especially regarding the customer’s experience with your company and product and touching on the overall impression they have of your brand. Depending on your product, this could be anywhere from a few days to a month or more after their first transaction.
Later, you can solicit feedback in a customer survey that focuses on overall product and brand satisfaction.