How to build an opted-in SMS contact list the right way

How to grow an SMS marketing list with proper consent: sign-up methods, wording, record keeping, importing contacts, groups and keeping your list clean.

Why quality beats quantity

It can be tempting to gather as many numbers as possible and start sending, but an SMS list is only valuable if the people on it want to hear from you. Texting people who did not agree leads to complaints, opt-outs, reports to their mobile network and potentially action from the Information Commissioner's Office. It also damages your reputation, because an unwanted text feels more intrusive than an unwanted email.

A smaller list of people who opted in will almost always perform better than a large list of reluctant or unaware recipients. They are more likely to read your messages, act on offers and stay subscribed. This guide covers practical ways to collect consent, what to say, how to keep records and how to organise contacts in Orbis SMS. It is general information, not legal advice, so take your own advice if your circumstances are unusual.

Where to ask for consent

The best place to ask is wherever customers already give you their details. Each point of contact is an opportunity to invite people to receive texts, as long as you make the request clear and separate from anything else they are agreeing to. Asking at the moment of contact also means people understand where their details came from when your first text arrives.

• Online checkout and account sign-up forms, with an unticked box for marketing texts.
• Booking forms for appointments, tables, classes or viewings.
• In-store or at reception, using a paper or tablet form that records consent.
• Events and exhibitions, with clear wording on the sign-up sheet.
• Your website, with a simple form for people who want offers by text.

Keyword sign-ups, where people text a word to a number to join a list, rely on receiving inbound messages.

Whichever method you use, train staff to ask in the same way every time. A customer who is pressured at the till, or signed up without being asked, has not given valid consent, and they are likely to opt out or complain. A friendly, consistent question such as would you like to hear about offers by text, with a genuine choice, builds a list of people who want your messages.

Wording that makes consent clear

Consent must be specific and informed, so your wording should say who will text people, what kind of messages they will receive and how to stop. Keep it short and honest. For example: Yes, I would like to receive offers and news from Harbour Home by text message. You can opt out at any time by replying STOP. Avoid vague phrases such as selected partners or occasional updates that do not explain what people are signing up for.

Keep marketing consent separate from service messages. Customers might be happy to receive delivery updates or appointment reminders but not promotions. A separate tick box for marketing texts lets them choose, and lets you send service messages to everyone who needs them while only sending promotions to people who agreed. Never make marketing consent a condition of placing an order or booking an appointment.

Keeping records you can rely on

If someone complains, you need to be able to show that they agreed. Record the date and time, the source, such as a website form or in-store sign-up, and the wording they saw. If your forms change over time, keep copies of previous versions. For paper forms, store them securely or scan them, and enter the details accurately when you import contacts.

Your records should also show opt-outs. When someone asks to stop, note when and how they asked and make sure they are not added back by a later import. Orbis SMS handles STOP opt-outs on the platform, but requests made by phone, email or in person need to be added to your suppression list too. Reviewing your records every few months helps catch gaps before they become problems.

Importing and organising contacts

Once you have consented contacts, you can import them into Orbis SMS using a CSV file exported from your website, booking system or customer database. Check the file before importing: remove duplicates, correct obvious formatting errors in numbers and leave out anyone without the right consent for the messages you plan to send.

Use groups to keep different types of contact apart. A common approach is to have separate groups for marketing subscribers, service-only customers and staff. You might also group contacts by location, interest or customer type, so campaigns stay relevant. Keeping groups tidy reduces the risk of sending a promotion to someone who only agreed to reminders, which is one of the most common mistakes businesses make.

Before every campaign, take a moment to check you are sending to the right group, and that recent opt-outs have been removed. Use templates for regular messages so the wording and opt-out instruction are always correct. These small checks take a minute or two but prevent the kind of mistakes that lead to complaints and unhappy customers.

What to avoid and how to keep the list healthy

Never buy, rent or scrape lists of mobile numbers. Bought-in data rarely has valid consent for your business, and the soft opt-in never applies to it. Using it is one of the quickest ways to attract complaints and enforcement. Be cautious too about numbers collected for one purpose, such as a competition, being reused for unrelated marketing without telling people.

Keep your list healthy by removing numbers that consistently fail to deliver, honouring opt-outs promptly and not over-messaging. If you have not contacted someone for a long time, consider refreshing their consent before sending a campaign. Send relevant, useful messages at sensible times, and people will be far more likely to stay on your list and act when you do text them.

This guide is general information, not legal advice. For guidance on your own obligations, see the ICO website or speak to a qualified adviser.

Frequently asked questions