SMS text marketing reaches almost every mobile phone without an app, which is its main advantage over WhatsApp and other messaging channels, and its main limitation too: plain text, short length, no read receipts. For companies selling to customers in more than one country, the practical question is which text channel to use for which contact. This article compares SMS with WhatsApp for business texting, explains how each behaves on the levelpartner.ai platform, and shows how to route messages to the channel each contact actually uses.
How the two channels differ in practice
SMS works on any mobile number. It needs no app, no account and no opt-in to a third-party service. Messages arrive as plain text, and links are the only rich element. Business sending from US numbers requires registration, and carriers filter content they consider spam.
WhatsApp requires the recipient to have the app. It supports images, documents, buttons and read receipts. Business messaging runs through an approved business account, and messages you start outside an open conversation window must use pre-approved templates. Inside a conversation the customer started, you can reply freely for a limited time.
Which channel suits which audience
US contacts mostly expect SMS for business messages, and WhatsApp use for business varies by community. UK contacts use both, and many prefer WhatsApp for conversations with smaller businesses and advisers. International clients, common for agencies and consultants, often prefer WhatsApp because it avoids international texting charges on their side.
For our four industries, a common pattern is this. Mortgage brokers and real estate firms in the UK see a lot of client conversation move to WhatsApp, especially when documents are exchanged. Agencies and consultants with US clients usually stay on SMS for reminders and short follow ups.
Before you start
- An SMS-enabled number for each country, with business registration complete where required.
- A WhatsApp business connection set up on the platform if you plan to use WhatsApp.
- A custom field for preferred text channel, with the options SMS and WhatsApp, on your forms and filled in for existing contacts.
- Consent for each channel, recorded separately.
How to set up channel routing
One workflow serves both channels: an If/Else reads the preferred channel field and sends the same message by SMS or by WhatsApp. Make sure replies from both land in Conversations with the same owner.
- Go to Automation > Workflows.
- Create a new workflow or open an existing one.
- Choose the trigger that should start the message.
- Add the Send SMS action on the SMS branch of the If/Else.
- Enter the message for SMS contacts.
- Add personalisation or a template where appropriate.
- Add the WhatsApp branch's action and any Wait steps as needed.
- Test the workflow with one contact on each channel.
- Publish the workflow when it is ready to run.
Imagine 3,000 active clients, of whom around 1,100 choose WhatsApp when asked on the onboarding form. Their document requests would move there, because clients can send photos of payslips in the same thread. Reminders and rate-expiry texts would still go by SMS to everyone else. Advisers would work from one inbox and never need to know which channel a client picked. The split is hypothetical.
What it replaces
Channel routing replaces the situation where advisers use WhatsApp on personal phones because clients prefer it, while the firm's official texts go by SMS from the CRM. That split leaves half the client conversation outside your records and walks out the door with the employee. Bringing both into Conversations keeps the history on the contact.
Time it takes
Setting up routing takes a day, mostly in preparing WhatsApp templates and updating forms. After that, the extra effort is in maintaining two template sets, which takes perhaps an hour a month.
The mistake most people make
Assuming one channel fits everyone. Forcing UK clients who prefer WhatsApp onto SMS leads them back to personal phones. Forcing US contacts onto WhatsApp means many never see the message. Ask, record the answer and route on it. For writing the SMS versions of your messages, see writing short marketing texts.
Sending a WhatsApp marketing message outside an open conversation without an approved template. It will not send. Prepare and submit templates before you build the workflow.
When SMS alone is enough
If nearly all your contacts are in the US, or your texts are reminders and short prompts, plain SMS is simpler and you can skip WhatsApp. If you have no one to maintain a second template set, start with SMS and add WhatsApp when clients ask for it. For the wider overview of business texting, read how SMS marketing works, for message volume planning see mass text marketing done properly, and for keeping one inbox for replies, see managing replies in two way SMS.
Troubleshooting
WhatsApp messages fail to send. The template is not approved, or the conversation window has closed. Use an approved template to restart the conversation.
SMS replies and WhatsApp replies go to different people. Assignment rules differ by channel. Set assignment at the contact level so both channels follow the owner.
International SMS is expensive. Contacts abroad are on SMS by default. Offer them WhatsApp on your forms.
Contacts receive the same message twice. The workflow sends on both channels. Check that the branch uses if/else, not two parallel actions.
Frequently asked questions
Is SMS or WhatsApp better for business text marketing?
Neither in general. SMS reaches everyone, WhatsApp suits contacts who already use it. Let contacts choose.
Do I need separate consent for WhatsApp?
Yes. Record consent for each channel separately, and respect WhatsApp's own rules on business messaging.
Can I see both channels in one place?
Yes. SMS and WhatsApp conversations appear in Conversations on the same contact record.
Are WhatsApp messages billed like SMS?
Both are billed as used as usage. The rates and the way conversations are counted differ by channel.