Reviews, testimonials and real proof strengthen trust, but only if they are true and used with care. Exaggeration, misleading selection and lack of disclosure create legal risk and loss of credibility. There is a way to use social proof effectively and honestly.
The essentials in a definition
Proof and reviews in the creative increase trust, but have rules. The Unfair Commercial Practices Directive and Omnibus Directive prohibit fake reviews and require transparency on how they are collected; the Portuguese Consumer Portal gathers information for the Portuguese market. Using real, verifiable, representative testimonials protects the brand.
Why proof works
Faced with an unknown brand, people look for signs that others have already chosen it and been satisfied. Star ratings, customer quotes, numbers and real images reduce uncertainty and speed up the decision.
In ads, they show that the promise is not just the brand’s but confirmed by third parties.
What to use
Reviews on independent platforms, quotes with a name (or initials) and context, cases with verifiable numbers, number of customers or orders, certifications and awards. Prefer specificity to generic praise: “I saved 3 hours a week” convinces more than “excellent service”.
Always keep the source and the date.
Honest social proof
- Gather verifiable reviews and cases
- Obtain permission and keep the source
- Place the proof next to the promise
- Measure the effect and update
Limits and rules
Do not invent or edit testimonials. Do not select only the positive ones in a way that gives a misleading impression when there are many criticisms. Obtain permission to use names, images and quotes. Disclose incentives (discounts, gifts) given in exchange for reviews.
Respect each platform’s rules and the law on commercial practices and reviews.
Social proof is only worth something when someone can confirm it.
How to apply it
Place the proof near the promise: beside the call to action, on the landing page, in the ad. Update regularly. Respond to criticism professionally: one well-written reply can convert more than ten compliments.
Measure the effect: compare versions with and without proof, by audience and stage.
Decision table
| Type of proof | How to use | Caution |
|---|---|---|
| Customer reviews | Quote with context and source | Do not select only positive ones misleadingly |
| Video testimonials | Written authorisation and identification | Declare incentives, if any |
| Customer numbers and results | Verifiable, dated data | Do not generalise isolated cases |
| Seals and certifications | Show the body and scope | Only if true and current |
Common mistakes to avoid
- Bought or company-written reviews. It is an unfair practice and may carry sanctions.
- “Typical” results that are not. State what is typical and what is exceptional.
- Outdated seals. Remove them when they expire.
How to measure the result
Compare conversion of ads with and without proof, and track the percentage of proofs with authorisation and documented source.
Limits and exceptions
Rules on reviews and testimonials vary by country, sector and platform, and this content is not legal advice. Even real reviews can become misleading if presented out of context or outdated. Periodically review the proof used, document authorisations and, in doubt, choose the most transparent path.
Illustrative example
Illustrative example: a services company asks real customers for permission to use testimonials, records consent, and shows in ads the quote with name and company (or initials, if they prefer). It states on the site how reviews are collected. Trust rises, and the company avoids any risk from misleading reviews.
In practice: checkpoints
Use real names and permissions.
Frequently asked questions
Can I show only the best reviews?
It is wise not to give a misleading picture of the whole. Be honest and respond to criticism.
Do I need the customer’s permission?
To use a name, image or quote, yes.
How do I use negative reviews?
By responding professionally and fixing what can be fixed.
Can I offer something in exchange for reviews?
With great care and transparency; incentives can make the review misleading if not declared. Check the rules.
Can I delete negative reviews?
You should not hide legitimate reviews to look better; reply and resolve.
Use real, verifiable, representative proof, with authorisation and source, and never fake or misleadingly selected reviews.
Sources and recommended reading
- Unfair Commercial Practices Directive (2005/29/EC)
- Omnibus Directive (2019/2161)
- Portuguese Consumer Portal (Directorate-General for Consumers)
Last editorial review: October 2026. Informational content; always confirm current conditions in the official sources before deciding.