Campaigns can go by email, SMS or WhatsApp. Email is included in your plan. Text and WhatsApp messages carry a per-message cost, so use them where the immediacy is worth paying for.
Best for anything with detail, images or more than one idea. Cheap enough to send regularly, easy to ignore. It can carry a proper offer with a link.
SMS
Useful for short, time-sensitive updates, such as an available appointment. Delivery does not guarantee that the recipient reads the message. Use consent and contact preferences to decide whether SMS is appropriate.
Sits between the two. More room than a text and more conversational, but it is a personal space and people notice when a business turns up in it uninvited.
The rule of thumb
Would you be pleased to receive this by text? If the honest answer is that an email would have done, send the email.
Cost control
Watch what you are spending on messaging. Settings, then Messaging Credit, shows your balance and spend this period and lets you set a monthly budget cap.
Common questions
Do I need separate consent for SMS?
Consent should cover the channel you use. Somebody who agreed to emails has not necessarily agreed to texts. The safest position is to be specific when you ask.
Which gets the best response?
SMS gets read most, email gets acted on most for anything needing thought. Use them for different jobs rather than picking a winner.
What happens if I run out of messaging credit?
Sends stop rather than silently failing. Check Settings, then Messaging Credit, to see where you stand.