Short answer. Ask every satisfied customer, once, at the moment the experience is freshest. For most small local businesses that works out to between five and fifteen review requests a week, which over a year quietly builds the review volume that actually moves local pack rankings.
The longer answer depends on your specific situation, so here is the real breakdown.
The right moment to ask is right after a positive interaction, when the customer's satisfaction is at its peak. For a restaurant, that is at the end of the meal when they are telling the server it was great. For a dental practice, that is as they check out after a clean visit. For a contractor, that is the final walkthrough when the work is clearly done right. The further the ask drifts from that moment, the lower the response rate.
For service based businesses where the work wraps up hours or days later, send the request within 24 hours of job completion while the experience is still current. Waiting a week is waiting too long.
Yes, with one filter. Ask every customer who is clearly satisfied. Do not ask customers who just had a bad experience, because you are inviting a one star review you would have otherwise avoided. Train your team to read the room. A happy customer gets asked. An unhappy one gets a follow up call to fix the issue first.
Some business owners get squeamish about "cherry picking" only happy customers, but this is not cherry picking. It is basic customer service. Solve the problem first, then ask for feedback once the customer is whole.
Google does not cap review requests, but the platform does penalize clearly fake review patterns. Asking too many customers within a short window, especially from the same IP address or device, can trigger review filtering. Google may suppress the reviews or flag the profile as suspicious. A steady cadence of five to fifteen real review requests a week, coming from different customers through different channels, is what looks natural.
If you suddenly jump from three reviews in a year to sixty in a week, expect Google to quietly hide most of them.
Automation is fine, overautomation is not. The cleanest pattern is a single request sent 24 hours after a transaction, then one reminder five to seven days later if the customer has not responded. No third request. No follow up nag. If they did not leave a review after two touches, they are not going to, and pushing further damages the relationship.
SMS outperforms email for response rate on most small business requests, but use the channel your customers actually prefer. If your customer base skews older or more traditional, email still works fine.
Asking for reviews is half the work. Responding to them is the other half, and both matter for local rankings. Our companion guide on how to respond to Google reviews covers the response side in detail. If you want the bigger picture on why reviews affect rankings in the first place, our post on whether Google reviews help SEO walks through the mechanics.
If you want help building review generation into your broader local SEO work, that is covered under our local SEO services.