ReviewHeroFollow-up review email: how to send one reminder
A follow up review email works best as one reminder. Wait a few days, honor opt-outs and never target by mood to stay inside Google and FTC rules.
The short version
- The best field evidence on reminders, two randomized experiments published in 2023, found that a reminder sent right away lowers the odds of a review and a delayed one raises them.
- No Google rule or FTC rule caps how many times you may ask, but every message you send is still a commercial email that needs a working opt-out.
- Because Google does not tell you who reviewed, you cannot safely aim a reminder at people who stayed quiet, so send the same message to everyone or to no one.
You sent the review request. A week later the count has not moved, and an obvious next step comes to mind: send it again. Whether that helps depends on how long you wait, who gets the second email, and what happens when someone says stop.
This post covers the follow up review email, meaning one reminder and no more, what the research says about it, and what the rules do and do not say. It does not cover sending a third.
Short answer
Send one reminder, a few days after the first message, to the same group that got the first. Include a working unsubscribe link and your postal address. Do not send a reminder to only the customers you think were happy, and do not offer anything in return for a review.
Does a reminder work?
The strongest evidence found for this post is a 2023 paper in the Journal of Marketing, Ask for Reviews at the Right Time (Jung, Ryu, Han and Cho, volume 87, issue 4; DOI 10.1177/00222429221143329). It reports two randomized field experiments covering more than 300,000 consumers. One ran on a large South Korean online travel marketplace and one on a South Korean apparel marketplace. Reminders went out after one, five, nine or thirteen days, and each test had a control group that got none.
Per the publisher's summary, a reminder sent immediately made a review less likely, which the authors tie to people reacting against being pushed. A delayed reminder made a review more likely, which they tie to the customer remembering the experience. Timing had little effect on the rating, the sentiment or the length of the review.
Three cautions. The paper is from 2023, not 2025. The customers were shoppers on Korean marketplaces, not people who hired a US plumber. And the press release gives no effect sizes, so this post cannot tell you how many more reviews a reminder buys. The direction is the useful part: waiting beats nagging.
Other research is less encouraging. Studies of survey response outside reviews have found that email reminders do not always help. One trial of 5,539 doctoral students, published in Field Methods in 2024, found that no email intervention raised overall response. That is a different task from leaving a review, so treat it as a reason for modest expectations and not as a prediction.
| Question | What the evidence supports |
|---|---|
| Does a reminder help? | Sometimes. Two large experiments found a lift when it was delayed. |
| Does sending it immediately help? | The same experiments found it lowered the odds of a review. |
| Does the reminder change the rating? | Timing barely moved rating or sentiment in those experiments. |
| How much does it help? | No dependable US small business figure exists. |
What Google's policy says about asking again
Google's Maps contributor policy, at support.google.com/contributionpolicy/answer/7400114, allows a business to ask customers for reviews that reflect a real experience. The page is undated; this post read it on 2026-10-31. It sets four limits that matter for a follow-up:
- You may not selectively solicit positive reviews from customers.
- You may not offer an incentive for a review.
- You may not discourage or prohibit negative reviews.
- You should not require or pressure people to review while they are on your premises.
The page does not mention reminders and does not cap how many times you may ask. Nothing in it says a second email is allowed or forbidden. The first limit is the one that bites. If your reminder goes only to the customers who rated you highly in a survey, you have selectively solicited, and that is a policy violation whether the email is the first or the fifth.
Google's help page on sharing a review link or QR code adds that customers must be signed in to a Google Account, and repeats that rewards for reviews are prohibited. A discount code in the reminder falls under that.
What the FTC rule says
The FTC's Consumer Reviews and Testimonials rule, 16 CFR Part 465, took effect on October 21, 2024. It was published at 89 FR 68034. Its suppression section, § 465.7, bars unfounded legal threats, physical threats, intimidation and knowingly or recklessly false public accusations aimed at stopping or removing a review. A polite reminder is none of those.
The FTC's questions and answers on the rule say you may email all purchasers and ask them for reviews. They also say the rule has no specific ban on asking only the customers you think are happy, but that doing so could still violate the FTC Act. That matches Google's selective-solicitation limit, and it is why the one safe pattern is to treat every recipient the same way.
The same Q&A says the rule does not prohibit incentives as long as they do not depend on the sentiment of the review. Google is stricter. For a business whose reviews live on Google, the working answer is no incentives.
Neither the rule text nor the Q&A addresses how many times you may ask. This post found no federal limit and will not invent one.
The part most people skip: CAN-SPAM
A review request is promotional more often than not. The FTC's CAN-SPAM compliance guide says the primary purpose of a message decides whether it counts as commercial, and review requests are not among the listed transactional categories. The reading in this post is that a reminder should be treated as commercial email. That is an inference, not an FTC statement about review requests.
Under 15 U.S.C. § 7704, each commercial message needs:
- A clear opt-out that works for at least 30 days after you send.
- A valid physical postal address.
- An honest From line and subject line.
Once someone opts out, you have 10 business days to stop. The reminder is where this matters most, because it is the message most likely to reach someone who is already tired of hearing from you. If the first email brought an unsubscribe, the second must not go to that person. The FTC's civil penalty is set per violating email, so a mistake in a list of 300 is counted 300 times.
For the full list of requirements, see what a review-request email must legally contain.
You cannot tell who already reviewed
The polite way to run a reminder is to send it only to people who have not reviewed yet. Nothing in the Google documentation read for this post links a review to the request that prompted it. The review link is a generic link or QR code, and reviews show a public name that may not match the name in your customer list. This is an inference from silence, not a Google statement, so check your own Business Profile before relying on it.
In practice that leaves two honest options.
| Option | Cost |
|---|---|
| Send the reminder to everyone who got the first email | Some people who already reviewed get a second, slightly redundant message |
| Send no reminder | You lose whatever lift a delayed reminder gives |
Two shortcuts to avoid: matching names by hand and skipping the reviewers you recognize, because the match will often be wrong, and sending the reminder only to people whose job went well, because that is selective solicitation.
The cleanest design is a short line that costs nothing: "If you have already left a review, thank you, and please ignore this note."
What a good follow up review email looks like
Keep it shorter than the first message. A workable structure:
- Subject: plain and specific, such as "Quick follow-up on your visit". No fake urgency and no "Re:" prefix that suggests a conversation that never happened.
- First line: one sentence that says why you are writing and that this is the only reminder.
- Body: the same single link as the first email. Do not add a second ask, a survey or a coupon.
- Close: thanks, a line for people who already reviewed, a real sender name, and a reply address a person reads.
- Footer: postal address and an unsubscribe link that works.
Send it a few days after the first message, not the next morning. The experiments above support waiting; they do not support a particular number of days as the best one, and this post will not name one. Pick a gap you can defend, such as one week, and keep it the same across customers.
If you handle sensitive services, check your own rules before you email at all. A medical or dental practice, for example, has extra limits on what a message may say; see Google reviews for medical and dental practices.
What we could not verify
Several figures are repeated across the web, and none could be traced to a primary source:
- Claims that a reminder "doubles" the response rate.
- Specific percentages for how many more reviews a second email brings. One ecommerce vendor reports a median 86 percent gain across 227 stores; it is observational vendor data, so this post does not cite it as proof.
- A Google rule on how many times you may ask.
- Any measured unsubscribe or annoyance rate for repeated review requests.
If you see one of these quoted as fact, ask where it came from. Our own look at review-request email claims found the same pattern.
How a tool should handle it
A tool that sends reminders should do four things without being asked: send one reminder, apply it to every recipient the same way, honor opt-outs before the next send, and carry the address and unsubscribe link in every message. ReviewHero is built around that last point, with a sender name, a reply path and a one-click opt-out on each email.
If you send by hand from a spreadsheet, keep a column for unsubscribes and check it before every send. It is the step most often forgotten.
Frequently asked questions about the follow up review email
How many follow up review emails should I send? One. No Google or FTC rule sets a number, but the research above supports a single delayed reminder and nothing supports a third.
How long should I wait before sending the follow up review email? A few days at least. In the two experiments, an immediate reminder made a review less likely and a delayed one made it more likely. No study named a best number of days.
Can I send the follow up review email only to customers who have not reviewed? You cannot tell who has, because nothing in Google's documentation links a review to a request. Send the same message to everyone who got the first one.
Do I need an unsubscribe link in a reminder? Treat it as commercial email: yes, with a working opt-out and your postal address, honored within 10 business days.
What to do next
- Wait a few days after the first request. Do not send the reminder the next day.
- Send the same short message to everyone who received the first one, not only the happy customers.
- Add a line thanking people who already reviewed and telling them to ignore the note.
- Put your postal address and a working unsubscribe link in the footer, and honor opt-outs within 10 business days.
- Remove any discount, gift or entry in a prize draw from the message.
- Stop after one reminder.
This is general information, not legal advice. Rules vary and change; talk to a lawyer about your own situation.
Put this on autopilot
ReviewHero asks every customer once, follows up politely, and stops the moment they open the review link. Free to download, and you can set it up from your phone.
