sms

Start with a compliance check: complete A2P 10DLC registration for US sends and set up a compliant opt-in flow with proper disclosure language. Then launch the abandoned cart sequence first since it is the highest-ROI flow, followed by post-purchase and win-back flows.

Klaviyo SMS is the default pick if you already use Klaviyo for email, since it shares one subscriber profile. Postscript offers the deepest Shopify-specific SMS features, while Attentive suits mid-market brands wanting full-service support.

No. Checkout phone capture only permits transactional messages about that specific order. Marketing SMS requires express written consent under TCPA, with clear disclosure, frequency expectations, and STOP/HELP instructions, or you risk $500-$1,500 per message in penalties.

Emojis, curly quotes, and accented characters force UCS-2 encoding, cutting the segment size from 160 GSM-7 characters to 70. A message over 70 characters then bills as two segments, doubling per-send cost. Preview segment count in your platform before scheduling.

Healthy opt-out rates are under 2% per send and under 0.5% for promotional sends. Higher rates signal over-sending or poor relevance; reduce frequency to 1-2 promotional sends per week and segment by engagement level.

Use a short code when your list exceeds roughly 100K subscribers or you need sustained throughput above 100 messages per second. Lists under 10K work fine on 10DLC, and toll-free numbers suit the 10K-100K mid-range.