Texts your customers signed up for, sent when they help.

Kashif works in Klaviyo and Mailchimp on client stores, and our Klaviyo email marketing service sets up the same consent and quiet hour rules this page describes. Every SMS setup is checked against Klaviyo’s help articles on SMS consent collection and US cart abandonment by SMS, read on 19 October 2026, and the work is logged so you can see what was set and when.

Ecommerce SMS marketing starts with consent, because a text without it is a legal risk, not a sale. Klaviyo’s guide to SMS consent collection sets the rules we build to: people must agree to texts specifically, SMS consent must be collected separately from email, it must never look required to buy, and a phone number on an order is not consent. Bought or shared lists don’t count either. We add a separate SMS step to your forms and an optional SMS checkbox at checkout, with disclosure text above it.

Next is the sending number. Klaviyo needs an active sending number in each country before it can collect SMS consent, and in the US a toll-free number has to be verified; Klaviyo’s page on SMS sending numbers compares the types. Klaviyo’s page on toll-free verification also warns that carriers expect a verified number to start sending soon, and a pause of several weeks can put it back to unverified. So we time the verification with the launch of the first flows, not weeks before.

Then quiet hours. Klaviyo recommends not sending between 9 p.m. and 8 a.m. in the recipient’s local time, with stricter rules in some US states, and notes that flows judge local time by the phone number’s area code. We set quiet hours on the account, check the time zone rule for flows and campaigns, and schedule campaigns for the late morning or early evening in the main time zone of your customers.

Flows come before campaigns, because they reach people at the moment a text helps. For abandoned cart texts, Klaviyo’s page on US cart abandonment guidelines lists what the TCPA, CTIA and carriers require: double opt-in, one SMS per recipient in the flow, sent within 48 hours of the trigger, with express consent and disclosures in your terms and privacy policy. Klaviyo’s double opt-in process handles the confirmation text. We build that flow to the letter, then add shipping updates, back in stock alerts and a welcome text where they fit your store.

Campaigns are fewer than most stores expect. Email can carry the weekly newsletter; text message marketing works best for things with a deadline, such as a launch, a restock of a sold-out bestseller or the last day of a sale. We plan two to four SMS campaigns a month for most stores, send them to engaged segments rather than the whole list, and keep every text short, with the brand name first and a clear opt-out.

Last, we judge SMS on what it adds. Each message is compared with the same message by email, and the report shows revenue, clicks and unsubscribes per text. If SMS isn’t earning its cost for a segment, we stop sending to that segment. Most of the value sits in a few flows, so a short, well-run program usually beats a busy one.