SMS templates are limited to 160 characters and don't support HTML code.
SMS messages are designed to be short and sweet, so they are not ideal for including full booking and arrival details. Instead, SMS messages can be used to send guests reminders or thank-you messages.
For example:
Hi [guestname], we're excited to have you arriving tomorrow!
Hi [guestname], we hope you're enjoying your stay. Please visit our website to leave a review.
Hi [guestname], don't forget to check out at 11am tomorrow.