AI features in email marketing tools, plan by plan

What does each AI feature do?

Subject lines: drafts you pick from

The tool writes several subject lines from your email or a short prompt. You pick one, or send two to a slice of your list and keep the one that gets more opens (an A/B test). Kit’s AI page says its generator also tests them inside the broadcast editor. MailerLite marks its free subject line generator as Limited, and its AI writing assistant starts on Comfort.

Email writing: a draft of the body

A text box in the editor drafts the body, rewrites a paragraph or changes its tone. GetResponse’s AI email generator is capped at “Up to 3 uses” on Starter and unlimited from Marketer (GetResponse pricing).

Segments: an audience described in words

You describe an audience in plain words, such as “bought twice, no order in 60 days”, and the tool builds the filter. Omnisend’s AI Segment Builder works from a written prompt, on every plan including Free.

Send time: one hour per contact

The tool picks a send hour for each contact from that contact’s past opens and clicks. Brevo’s pricing page describes it as sending “when each contact is most likely to engage”. Its marketing agent lists send at best time next to content generation and smart segmentation.

Predictions: scores built from order history

Scores for each customer: next order date, expected spend, chance of leaving. These need history. Klaviyo’s lifetime-value predictions need three things. The store has “at least 500 customers” with an order, 180 days of order history with orders in the last 30 days, and some customers with three or more orders (Klaviyo help, updated 5 August 2025).

Product picks: a block of likely buys

A block in the email shows each customer the products they are most likely to buy. Brevo puts it on Professional; GetResponse on Enterprise.

Agents: AI that does several steps

An AI that carries out several steps for you: building a campaign, writing a sequence, answering replies. Five of the 12 tools list an MCP server: Brevo, Kit, MailerLite, Omnisend and beehiiv. An MCP server is a connector that lets ChatGPT or Claude read your account and act on it. MailerLite’s terms (clause 17.2) say connecting one authorises it to read and modify your account data.

beehiiv gives its agent read access on every plan and write access from Lite.

Kit runs its AI Connectors on Creator and says it does not train AI on Kit data.

AI Connectors, security and data FAQ

Kit itself does not train any AI/LLM on Kit data. Please note, however, once a creator connects AI Connectors to a third-party AI client (ChatGPT, Claude, Gemini, etc.), that provider’s own data-handling settings govern whether prompts/data get used for model training.

This creator walks through the AI features of several email marketing tools in one video.

BEST AI-POWERED EMAIL MARKETING TOOLS IN 2026Oyundoyin Anthony

Which plans include the timing and prediction features?

Send time and predictions are where the AI in email tools gets expensive. The cheapest send time model is Brevo Standard at $18 a month. HubSpot keeps it for Enterprise, from $3,600 a month billed annually, for 10,000 marketing contacts. Entry prices hold the smallest list each plan sells, so check yours on email marketing prices by list size.

Prices are in USD a month. HubSpot Enterprise is billed annually and adds a one-time onboarding fee; every other row is billed monthly. ActiveCampaign is left out of this table because it publishes yearly billing only: account-based send times sit on Plus, predictive sending on Pro.

Klaviyo is the outlier for a store: its first paid plan carries predictive analytics. Mailchimp puts predictive segments on Standard, its second paid plan.

Is Mailchimp AI included in every plan?

No. Mailchimp’s pricing page lists its Generative AI Features as a “No additional cost add-on” on Standard and Premium and “Not included” on Essentials and Free. Standard starts at $20 a month for 500 contacts (checked 6 November 2026). Predictive segments sit on Standard and Premium, says a pricing page footnote.

The pricing page does not mention send time optimisation, a subject line helper or product recommendations, so they appear as “Not listed” above. Section 30 of its terms covers what Mailchimp may do with your AI inputs. That clause is quoted in does your email tool train AI on your list.

What does Klaviyo AI include?

Klaviyo groups its AI features under a sparkle icon. The free plan generates subject lines and gives Composer, its marketing agent, $5 of usage.

The Email plan card lists “AI-generated segments, content, and images”, plus predictive analytics. Composer’s add-on costs $20 a month for four times the usage (checked 6 November 2026).

Klaviyo bills active profiles, so every sign-up you keep counts towards the price. For a store choosing between Klaviyo and its rivals, see the best email marketing for ecommerce.

Does HubSpot have an AI email writer?

Yes. HubSpot’s product catalogue lists Breeze Assistant, which can “generate content” inside the CRM, but its edition marks are icons, so the lowest plan is not readable. HubSpot’s own page labels its AI Email Writer beta, and its Generate content dialog box asks for the email type, product, audience and tone.

The Content agent (Beta) needs Professional and draws on HubSpot Credits: 3,000 a month on Professional, 5,000 on Enterprise. Send time optimisation (Beta) is Enterprise only.

What do the AI writers in cold email tools add?

Instantly and lemlist sell AI for outreach to people who never signed up. Instantly’s AI Reply Agent sits on the Scale bundle. It spends 5 credits per reply.

lemlist runs its AI Copilot on Claude, per its AI information page, and lists lemAgent on the Email plan. Price per mailbox and warm-up decide more than the AI here: see the best AI cold email tools.

What the AI in email tools does not do

None of these features knows your list on day one. A send time model works from each contact’s past opens and clicks, so a new subscriber gives it nothing to work from. Klaviyo’s lifetime-value predictions stay blank until a store meets all three order-history conditions above.

A generated subject line is a suggestion. No pricing page in the table promises a higher open rate from it, so you still test it against your own line.

The AI email marketing hub groups every page of this section. The best AI email marketing tools ranks the generalists by price at your list size.

Every AI feature, its plan and its limits

Questions buyers ask about AI in email tools

Does Omnisend have an AI subject line tool?

Yes. Omnisend’s AI page says its free plan includes AI-generated subject lines and preheaders, with no credit limit stated.

Does GetResponse have an AI email generator?

Yes, capped at 3 uses on Starter and unlimited from Marketer, per its pricing page. Marketer starts at $59 a month for 1,000 contacts (checked 6 November 2026).

Which email tool has free AI writing?

Omnisend’s free plan writes subject lines and email copy. Klaviyo’s free plan and MailerLite’s free plan (marked Limited) generate subject lines.

Every AI email marketing page, sorted by job, is in the AI email marketing hub →