Constant Contact vs Campaign Monitor: a small-business suite or an agency-and-developer email tool

Campaign Monitor's price grid

Campaign Monitor's pricing page was read on 7 October 2026 at four contact stops, on both billing toggles. The first figure is monthly billing and the figure in brackets is annual billing, per month.

Lite caps sending at 5 times your subscriber count, which is 12,500 emails at 2,500 contacts and 50,000 at 10,000. Essentials removes the cap and adds priority support, and Premier adds phone support. Moving from Lite to Essentials costs $18 at 500 contacts, $27 at 2,500, $42 at 5,000 and $65 at 10,000, so the unlimited-send step gets pricier as the list grows. The annual discount on Essentials at 10,000 contacts is $218.40 a year (182 times 12 is $2,184, against 163.80 times 12 at $1,965.60).

Constant Contact's plans

Constant Contact publishes starting prices and says your exact price depends on how many contacts you hold. Its page lists these, read on the same date.

The page text I could read stops at starting prices, so a like-for-like figure at 5,000 contacts means entering your list size in Constant Contact's own selector. Other costs it lists: SMS on Lite or Standard starts at $10 a month for up to 500 messages, and nonprofits get 20% off with six months prepaid or 30% off with twelve. Every paid plan carries a 30-day money-back guarantee.

Where the products differ in practice

• Seats. Campaign Monitor's grid lists unlimited users on all four plans. Constant Contact moves from one user to three to unlimited, so a marketer plus a developer plus a founder already pushes you to Standard.
• Support. Constant Contact's table shows live phone and chat with marketing experts on Lite, repeated on Standard, with a dedicated priority team on Premium. Campaign Monitor puts priority support on Essentials and phone support on Premier.
• Extras. Constant Contact adds social posting, a social ads manager on Standard, hosting events and taking payments, and lists 300-plus integrations. Campaign Monitor lists 250-plus integrations, custom-coded templates, drip campaigns and an inbox preview feature.
• Templates. Campaign Monitor's Lite card includes custom-coded templates and unlimited signup forms. Constant Contact leans on its drag-and-drop editor, AI copy generator and template library.

Billing events: trial end, failed payment, upgrade, cancel

A SaaS product sends a few messages from its own code rather than from a marketer's calendar, and here the two split. Campaign Monitor's transactional API has a smart email send: you design the email in Campaign Monitor, then POST to the smart email's send URL with a recipient and a Data object whose properties become template variables. A success returns 202 with a message ID per recipient, each call allows 25 recipients across To, CC and BCC, and Data is capped at 100 KB. The docs list an active monthly plan and a matching, authenticated sending domain as account requirements for transactional sending.

That maps cleanly onto a Stripe invoice.payment_failed webhook: your server receives the event, then calls the smart email with the customer's first name, the amount and a card-update link. Constant Contact's V3 API is organised around contacts, lists, tags, custom fields, segments and email campaigns. The docs I read describe no per-event trigger, so the nearest route from billing there is to update a tag or custom field on the contact and build an automation around it, within the one-template and three-template limits on Lite and Standard.

Switching between them

1. Export contacts with custom fields and keep unsubscribed addresses in their own file, to be imported as unsubscribed.
2. Rebuild signup forms first, since they feed everything else, then recreate automations one at a time and compare against the old send logs.
3. Add the new platform's DKIM and SPF records before the first send and keep the old ones until a full cycle of mail has gone out.
4. If you adopt Campaign Monitor's transactional API, send from a subdomain you will not use for newsletters, so a spam complaint on one stream cannot touch the other.

Which to choose

• Constant Contact fits a shop, clinic or association where the owner wants email, social and events in one login and prefers a human on the phone.
• Campaign Monitor fits an agency managing client lists, or a software company that wants unlimited seats, coded templates and a send-from-code endpoint.
• Neither is built around product events. If trial and plan data should drive the sequences, see how Mailchimp compares with Campaign Monitor or look at tools priced by profile.

Related reading: all comparisons, Mailchimp vs Constant Contact, Brevo vs Constant Contact, MailerLite vs Constant Contact and the email marketing category.