Pick Customer.io if
lifecycle teams who will start on Essentials at $100 / month (5k profiles, 1 million emails) while they open a first Consent state, then book Premium at $1,000 / month yearly when they want custom volume and HIPAA.
Read the Customer.io pagePick Loops if
saaS teams who will stay on Free $0 (1,000 subscribed contacts, 4,000 marketing+transactional sends / 30 days, Loops footer, 10 emails/sec, no card) while they send a first onboarding mail, then land on Growth at $49/month (starts at 5,000 subscribed contacts on the card we fetched; slider continues) when they need unlimited sends and the branding off.
Read the Loops page