Win Back Old Customers with SMS and WhatsApp

Why should I contact past customers before paying for new ones?

Because your past customers already know you, and you already hold their details. Most owners put their budget into finding strangers while hundreds of people who once paid them sit untouched in a booking system or spreadsheet. A reactivation campaign costs a few pounds in messages. It is usually the cheapest revenue you can add.

The familiar claim that winning a new customer costs 5 to 7 times more than keeping one is unsourced, so treat it as a rough benchmark, not a fact. The direction still holds. Braynex Services sees small businesses lose money in places they cannot see, and old customer data that is never followed up is one of the biggest.

Do I actually own my customer list?

Only if the data lives in a system you control. If your customers book through Fresha, Booksy or a Facebook page, the platform holds the relationship, and you may be unable to export numbers with consent records or message them freely. You can't reactivate a list you can't reach.

A nail salon we worked with was paying Fresha about £1,800 a month in commission. It moved to its own booking system at £35 a month, saving roughly £21,000 a year. The bigger gain was that every client record now sat in a system the salon owned, ready for exactly this kind of follow-up. Renting convenient platforms has a hidden cost: you pay for the customer, then you can't contact them.

Am I allowed to text past customers under UK rules?

Yes, if you have either fresh consent or a valid soft opt-in. Marketing texts count as "electronic mail" under PECR, so you can't simply message everyone in your phone contacts. The rules are strict, and penalties have risen sharply.

The soft opt-in lets you text past customers without new consent, but only if all three conditions are met:

1. You collected their details directly during a sale or sale negotiation.
2. You are only marketing similar products or services.
3. You offered a simple opt-out when you collected the details and include one in every later message.

Bought-in lists can never use it. Someone who enquired but never bought is on shakier ground, so check how their details reached you.

What counts as valid consent if the soft opt-in does not apply?

Consent must be freely given, specific, informed and unambiguous, with a clear affirmative action. Pre-ticked boxes, silence and inactivity don't count. It must name your organisation and cover texts specifically, not just "direct marketing" in general.

Keep a record of who consented, when and how. If the Information Commissioner's Office ever asks, "I think they agreed" is not evidence. A timestamped field in your booking or CRM system is. Under the Data (Use and Access) Act 2025, the maximum PECR fine rose from £500,000 to £17.5 million or 4% of global turnover, matching UK GDPR. Weightmans reports this took effect on 5 February 2026. Sloppy campaigns are no longer a small risk.

Can I message past customers on WhatsApp too?

Only if they have given you their number and given opt-in permission for WhatsApp. WhatsApp's Business policy puts responsibility for that opt-in on you. The PECR soft opt-in does not satisfy it, so a customer you may legally text is not automatically someone you may WhatsApp.

My view: start with SMS under the soft opt-in, and treat WhatsApp as a channel you earn. Meta's best practice is opt-in that covers each message category, such as offers, with a separate opt-in for calls. Add a WhatsApp tick box to your booking form now, so next year's list is ready.

How much does WhatsApp cost compared with SMS?

WhatsApp Business has charged per message since 1 July 2025, and only for delivered template messages. Marketing, utility and authentication messages are priced separately, with rates varying by recipient country. Meta's page says the UK marketing rate was raised effective 1 July 2026.

Check the current rate card before you budget. Outside an open 24-hour customer service window you can only send pre-approved templates, so a cold reactivation message must be a template. Once a customer replies, the window opens and you can chat freely. That makes WhatsApp strong for conversations and SMS simpler for a first nudge.

What should a reactivation message say?

Keep it short, personal and specific, with one clear action. Name your business, use the customer's first name, say why you're getting in touch, and make replying easy. Avoid shouting, vague discounts and links to a generic homepage.

Hi Sarah, it's Emma at Studio 9. It's been a while since your last visit. We have a few Thursday slots free this month, and I can book you in if you reply YES. Reply STOP to opt out.

That message has a named sender, a real reason, a one word reply and a free opt-out. A text "STOP" opt-out must cost nothing beyond the normal price of sending a message. Honour it immediately, and keep suppression lists per channel, because a text opt-out does not automatically cover email.

When is the best time to send, and how often?

Send once, on a weekday late morning or early evening, and follow up a single time after about a week to people who haven't replied. Don't build a drip sequence. Reactivation is a nudge, not a campaign, and every extra message raises your opt-out rate.

Send in small batches of 50 to 100 rather than the whole list at once. You'll learn what works, and you won't flood your diary. Prioritise customers who last bought 3 to 12 months ago: lapsed enough to need a reminder, recent enough to remember you. Clean the list first by removing anyone who has opted out, bounced or complained.

How do I measure whether it worked?

Track replies, bookings, opt-outs and revenue against the cost of sending. Ignore open rates. Vendors claim SMS open rates of about 90 to 98%, against roughly 20 to 43% for email, but Practical Ecommerce points out the figures are inflated because a message must be tapped even to delete it.

Use these four numbers for each batch:

• Reply rate: replies divided by messages delivered.
• Booking rate: confirmed bookings divided by messages delivered.
• Opt-out rate: if it climbs, your message or targeting is wrong.
• Revenue per message sent: the figure that tells you whether to repeat it.

Use a dedicated booking link or a code word per batch so you can attribute the revenue honestly.

What is the biggest mistake owners make?

Treating the list as a one off blast instead of a system. The owners who benefit set up a simple, repeatable process: capture consent at booking, store it with a date, and trigger a message automatically when a customer has been quiet for a set period. That is what Braynex Services builds for clients, because a reactivation campaign you run once a year by hand rarely survives a busy month.

If you'd like to know what your old customer data is worth, and whether your consent records would stand up to scrutiny, book a free audit at braynexservices.com. We'll look at your booking setup, your list and your follow-up, and tell you plainly what to fix first.