Apollo vs Seamless.AI

Reachkit makes a competing cold email tool with a built-in lead database. Apollo’s figures below come from its own pricing data and help center, checked in October 2026. Seamless publishes no prices and its terms bar competitors from using it, so nobody at Reachkit has an account; its figures come from its public site, help center and terms, and any third-party number is named as such.

My verdict: Apollo is the easier of the two to buy, test and leave, and Seamless.AI earns its place with sales teams that dial as much as they email and are used to yearly software deals. Apollo shows its prices, keeps a free plan with no end date and wraps warmup, bought mailboxes and bounce limits around its 240M+ contacts. Seamless sells by quote on annual plans, and one lookup credit returns a person’s emails and phones together, where a mobile on Apollo costs 8 credits.

Pick Apollo if:

• You’d like to test the data for free and keep paying monthly.
• Email is a big share of the work, and warmup, mailbox buying and a bounce guard should live in the same tool.
• Seeing the price before any sales call matters to you.

Pick Seamless.AI if:

• Reps prospect from LinkedIn in Chrome and spend much of the day on the phone.
• Your company already signs yearly deals and someone can own a renewal date two months out.
• A big team needs one package: Enterprise was listed with unlimited users.

Checked October 2026, from each vendor’s site, help center and terms; Seamless prices from the reviewers named under “What it costs”.

Apollo keeps and sells a database of its own, while Seamless.AI says it researches each person live at the moment you ask.

Apollo counts 240M+ contacts across 30M companies, drawn from more than 2 million contributors who share data, a web crawl and outside providers. Since December 2025 a waterfall step asks extra vendors by default when a record is thin, which can cost more than one credit, and Bombora intent signals arrived in June 2026. You pay only for verified emails, which Apollo calls 91% accurate in its help center and 98% in its AI fact sheet, and a bounce within 30 days on an email sent through Apollo earns the credit back; mobiles never do.

Seamless calls itself “a real-time search engine, not a database”, yet its pages quote totals that disagree: 1.8B+ verified emails on the homepage, 1.3B+ verified contacts on the bulk credits page. Each email is tagged from Valid through Accept All to Do Not Mail and scored for confidence. Credit Back Protection returns the credit when Seamless’s own check rules an email invalid, though the help center reserves the right to limit refunds, and its AI fact sheet tells buyers to test small batches first.

I wouldn’t plan around either vendor’s accuracy claim. A few hundred contacts from my own niche and a bounce count tell me more.

Apollo has spent the last year turning sending into a full setup around its data, while Seamless.AI’s Connect sends from inboxes you already own and leaves warmup to another vendor.

Apollo. Google and Microsoft mailboxes connect with a sign-in, others over IMAP and SMTP. Apollo also sells domains and Google or Microsoft mailboxes for credits and writes the SPF, DKIM and DMARC records itself; bought mailboxes top out at 200 sends a day and should warm six weeks or more first, Apollo says. Warmbox.ai, an outside service, does the warming, free for one mailbox per seat and 200 credits a month for each extra. Apollo suggests starting each mailbox at 50 emails a day, holds a mailbox for review at 4% bounces and stops it at 6% by default, and has blocked catch-all addresses since September 2026. Basic allows one mailbox and 250 sends a day per user, so most senders end up on Professional.

Seamless.AI. Connect, which the archived pricing page showed on every plan, runs sequences from as many Gmail or Outlook inboxes as you link and spreads sends across them. Nothing caps an inbox by default. The help center recommends 250 or fewer a day and allows 1,000, and for warmup it points you to “a Reputable Warm-Up Service”. Seamless sells no domains or inboxes.

I’d never push one cold inbox anywhere near 250 a day. On Connect, set a far lower limit yourself.

Apollo is built to be the screen a rep works from all day, while Seamless.AI is built to grab a contact from whatever page a rep has open.

Inside Apollo sit sequences, a reply inbox sorted by sentiment, a dialer, a meeting scheduler, call recording and deals. Sequence rules decide whether a reply stops that person’s sequence, and an out-of-office pauses it. Salesforce and HubSpot sync both ways on every plan, and Pipedrive, Zoho and Dynamics connect too. All seats share one plan and one credit pool, with per-user caps. A recurring G2 con is an interface some find overwhelming.

Seamless’s Chrome extension runs on LinkedIn and company sites: Find spends a credit, then you push the person to a list, an export, your CRM or a Connect sequence. Connect adds tasks and calling, which needs a Twilio subscription. The help center has setup guides for Salesforce, HubSpot, Dynamics, Pipedrive, Zoho, Outreach and Salesloft, plus Bullhorn and Greenhouse for recruiters, and admins can cap each user’s draw on a shared pool. G2 reviewers single out how easy it is to use.

Both have opened their data to AI assistants, but Apollo bundles more of its AI into the plan price, while Seamless charges a fraction of a credit each time.

MCP is a connection that lets an assistant like Claude or ChatGPT search a tool and act in it for you. Apollo’s MCP server works on every plan, though Free needs a company email domain and handles saved contacts and single lookups, and prospecting the database needs a paid plan. Its AI Assistant is uncapped on paid plans and asks before spending credits. Agents, added in September 2026 on Professional and Organization, find leads and write and refine sequences on a schedule within a per-run credit limit. Apollo’s developer docs put the API on every plan; its pricing FAQ says Custom plans.

On Seamless, each AI Assistant interaction and each AI Campaigns message costs 0.2 credits, and Autopilot charges 1 credit per contact it lists. The API has been open on every plan, free included, since May 2026, at 60 requests a minute, and the MCP integration for ChatGPT and Claude may draw credits. Seamless also feeds HubSpot’s Breeze Prospecting Agent and ships an n8n node. Its homepage lists “AI Agents”, which I found no help-center pages for.

You can buy Apollo by the month and walk away when a month ends, but every Seamless.AI plan is a yearly commitment, and that gap outweighs any feature here.

Apollo. A monthly plan can be cancelled anytime and runs to the end of the paid month. Paying yearly saves up to 24%, but there’s no refund or mid-cycle downgrade, and the plan renews unless you give notice 30 or more days before it ends. Apollo’s pages disagree on seats: the terms say you can’t cut seats during a term, the pricing FAQ says seat decreases are immediate.

Seamless.AI. The terms call every subscription annual, “with monthly or annual billing cycles”, and say “all sales are final”. To stop a renewal, an admin or owner files a request in the app and meets a Customer Success Representative, both at least 60 days before the date; miss it and you’re in for 12 more months. Seamless can also change prices “effective immediately upon notice”, charges 2% on late payments and can send unpaid bills to collections.

Neither lets you resell its data to clients under the standard terms. Seamless goes further and makes you destroy its data once you leave.

Because Apollo prints its prices, I can cost out both of my usual setups on it to the dollar. Seamless quotes every paid plan and has no inboxes for sale, so its column holds what the public record supports.

How I got there: about 4,000 emails a month for the founder and 25,000 for the agency, one credit per new contact, Apollo’s warmup, Google mailboxes and domains (spread over 12 months) paid in credits at add-on prices (a range, since Apollo doesn’t say how its volume tiers stack), and Reachkit at its posted inbox, domain and top-up prices.

For Seamless, Lindy (January 2026) and UpLead (October 2026) put Basic near $147 a month on yearly billing; UpLead’s Pro range is for teams of five or more, and Amplemarket (2026), citing other estimates, gives $147 to $299. The help center says Pro includes 10,000 credits a month, an archived pricing FAQ said 10,000 a year, so check the quote. Add a warmup service for your own inboxes, and monthly billing on Seamless still sits inside a 12-month contract.

Count 2 credits per email, as Apollo’s calculator does, and its second row rises about $27. Phones come inside every Seamless credit and cost 8 credits each on Apollo. Reachkit’s Growth plan holds 5,000 contacts, full around month four for the founder, and Scale’s 25,000 last the agency about 2.5 months, so you clear old leads or upgrade.

G2 reviewers rate both tools highly, but on Trustpilot the two split apart, and Seamless.AI’s low score there is driven by renewal disputes.

Apollo, as of October 2026, holds 4.7 on G2 across roughly 9,800 reviews, 4.5 on Capterra across about 400, and 3.1 on Trustpilot across about 1,370. Capterra users give customer service its weakest mark, 4.2. G2 reviewers praise the size of its verified contact database. Repeat complaints are verified emails that bounce, credit use that’s hard to predict, and slow support.

Seamless.AI, as of October 2026, holds 4.4 on G2 across more than 5,400 reviews, 4.5 on Capterra across more than 580, and 1.2 on Trustpilot across 311. G2’s summary credits it with ease of use and accurate contact data. Trustpilot reviews keep returning to renewals, above all the sales call needed before you can decline another year. Capterra’s theme summary rates 62% of 42 reviews on contracts and billing as negative and lists inconsistent contact data accuracy among the cons, with outdated emails and phones named.

This is our product. If the point of choosing between Apollo and Seamless.AI is to find people and then email them, Reachkit covers both jobs in one cold email tool you pay for monthly.

• Finding people. Lead Finder covers 500M+ people and 70M+ companies, and searches are free. A lead costs 1 credit once its email checks out, and the credit comes back on its own if none can be verified. Leads go into a campaign the AI writes from a one-sentence brief.
• Inboxes. Reachkit registers and configures domains for you ($15 a year) and sets up Google Workspace or Microsoft 365 inboxes ($5 a month), each warmed by AI at no extra charge. Inboxes you bring carry no per-inbox fee.
• Pace. A fresh inbox sends 3 emails on day one and adds 3 a day up to 20, and campaigns pause at a 5% bounce rate.
• Price. Growth is $39 a month for the workspace, with 1,000 credits and any number of teammates, cancellable anytime.

There are no phone numbers, dialer, Chrome extension, intent signals or Salesforce sync in Reachkit, so teams that live on calls should stay with Apollo or Seamless. More in Reachkit vs Apollo and the Seamless.AI tool profile.

Going from Seamless.AI to Apollo is mostly about the calendar and your rights to the data, and going the other way is mostly about Apollo’s bought mailboxes.

• Contacts. Apollo lets you keep using contact details you pulled into your own records while subscribed. Seamless’s terms say to “immediately securely destroy” its data on exit, so expect to look those people up again.
• CRM. Both work with Salesforce, HubSpot, Pipedrive, Zoho and Dynamics, so deals and activity stay put.
• Inboxes. Inboxes used with Connect are your own Gmail or Outlook accounts, so they plug into Apollo with their sending history intact. Apollo says mailboxes bought through it “may be deactivated” when credits run out or the plan changes, and it documents no way to transfer them out.
• Sequences. Expect to rebuild your steps by hand.
• Deadlines. Seamless wants the request and the meeting 60 days before renewal; Apollo’s yearly plans want 30 days’ notice.

For most people reading this, I’d try Apollo first: the free plan lets you test the data, monthly billing keeps you free to leave, and its sending comes with the limits that Seamless leaves for you to set. Seamless is a fair pick for a team that lives on the phone, buys software yearly and has someone watching the renewal date. Whichever you test, measure bounces on a sample from your own market before you sign. If cold email is the whole job, give Reachkit a 30-day trial.

Related reading: Reachkit vs Apollo, Apollo vs ZoomInfo, Apollo vs Clay, Apollo alternatives and the Seamless.AI profile.