Everything people ask about Sender Pools.

Sender Pools is cold email infrastructure that includes the infrastructure. Domains, Google Workspace, Microsoft 365 and SMTP mailboxes, warmup, rotation, email verification and AI-written sequences are all included at no extra cost, and you pay per send starting at $0.02.

You upload an ideal customer profile (ICP) and a contact list. Sender Pools provisions and warms the mailboxes, writes and times every email, verifies each recipient before sending, and rotates out any mailbox whose performance dips.

Four steps. First, you upload your ICP and your contacts. Second, Sender Pools buys domains and builds Google, Microsoft and SMTP mailboxes for you, sized to deliver your contacts inside a roughly 30-day window with about 50% extra as a buffer. Third, it warms the mailboxes, writes and times each email, and verifies every recipient before a send goes out. Fourth, it monitors every mailbox and replaces any that underperform, automatically and at no cost.

Anyone running cold email outbound who does not want to buy, configure, warm and babysit domains and mailboxes: founders, sales teams, lead generation agencies and growth teams. Plans start at 2,000 sends a month and scale past 1,000,000 sends a month, so it fits a first campaign and a large agency equally.

Every plan includes free .com secondary domains, free Google Workspace, Microsoft 365 and SMTP mailboxes, continuous warmup, automatic mailbox and domain rotation, auto scaling of infrastructure with results, drip sequencing timed to the recipient, AI copywriting for the first and second touch, email verification before every send, and a merged inbox that collects replies from every mailbox in one place. You pay only for sends.

Both. Legacy setups pair a sequencer such as Smartlead or Instantly with separately purchased domains and mailboxes. Sender Pools replaces the whole stack: it provides the infrastructure, the sequencing, the copy, the verification and the inbox, and charges one per-send price for all of it.

The app lives at https://app.senderpools.com. Sign up at https://app.senderpools.com/_auth/register and log in at https://app.senderpools.com/_auth/signin. There are no onboarding fees and no minimum contract.

Yes. Book a live demo with a deliverability expert at https://savvycal.com/senderpools/demo, or email hello@senderpools.com.

Pricing is per send, not per mailbox or per seat. Plans start at $40 a month for 2,000 sends, which is $0.02 per send. $40 is the minimum monthly spend. The per-send rate steps down as volume grows: $0.02 up to 25,000 sends a month, $0.018 from 30,000, $0.016 from 150,000 and $0.014 from 750,000 to 1,000,000 sends a month. Above 1,000,000 sends a month pricing is custom. Yearly billing saves 20%. Plans are month to month with no onboarding fees, and you can cancel anytime.

One send credit is one email sent from your pool of mailboxes. Domains, mailboxes, warmup and verification are already free, so send credits are the only thing that pays for outreach. A 2,000-send plan reaches up to 2,000 contacts with a single touch, or fewer contacts across a multi-step sequence.

Each plan bundles three kinds of credits sized from the advertised send count: send credits (1× the plan number), email verification credits (3×) and AI copy credits (5×). A 2,000-send plan, for example, includes 2,000 sends, 6,000 verification credits and 10,000 AI copy credits.

The infrastructure is free on every plan: domains, mailboxes, warmup and setup cost $0. Sending is paid, starting at $40 a month for 2,000 sends, month to month, cancel anytime. Referred users start with 1,000 free credits, and referrers earn 1,000 credits per signup.

Yes. Yearly billing takes 20% off the monthly price. On an annual plan you receive the full year's credits upfront and draw them down as you go; unused credits expire at the end of the 12-month term.

Yes! If you're on a monthly plan, any unused credits do roll over month-to-month, up to a maximum of 2× your monthly credit allocation. Once you hit that cap, you won’t accumulate additional rollover credits until you use some of the existing ones.

If you're on an annual plan, you receive your full year’s worth of credits upfront. There’s no monthly allocation or rollover — you just draw down from your annual pool as needed. Any unused credits expire at the end of your 12-month term.

If you purchase top-off credits (available only with an active subscription), those also roll over and are subject to the same 2× cap if you’re on a monthly plan. Top-off credits are always tied to the type of plan you’re on — monthly or annual — and expire based on your plan’s billing cycle.

Keep in mind: if you cancel your plan, any remaining credits (including rollover and top-off) will expire at the end of your current billing cycle.

Yes, we buy domains and create mailboxes from Google, Microsoft, and SMTP for you—for free. Our pricing is all-in-one, so there are no hidden fees.

Yes, here's how it works. When you upload your contacts, we automatically send to every contact you upload within 30 days. Over those 30 days, things happen, and some of your mailboxes and domains will inevitably get burned. When they do, we automatically and dynamically replace them at no cost to you, so in practice it truly feels unlimited.

We also build in a buffer from day one. We actually build about 50% more mailboxes and domains than you typically need for your 30-day sending window, so you're covered before anything even burns.

Sender Pools does have a fair use policy: we'll replace up to 50% of your mailboxes and domains every month, automatically, no questions asked. Between the built-in buffer and the way we send, you should never come close to burning through 50% of your domains and mailboxes in a month. If you do, cold email probably isn't for you and you may want to unsubscribe. For everyone else, 50% monthly replacement is way more than generous: it means you're effectively getting a completely fresh set of mailboxes every two months.

Yes, we warmup all of the domains and mailboxes properly.

We truly have access to the cheapest cold email mailboxes on the planet. First, we own the world's best SMTP mailbox infrastructure and have also figured out how to get very affordable Google and Microsoft mailboxes, allowing us to pass those savings on to you. A lot of cold email gurus will say to send only 5–10 emails per mailbox to ensure good deliverability, but we actually monitor every single mailbox for top-tier performance. In some cases, we're able to send more emails from a specific mailbox, helping you use fewer domains and mailboxes overall.

We have quite good deliverability because we're auto-balancing mailboxes and blacklist checks automatically. A lot of cold email tools will tell you what's wrong and suggest what to change, but we just do it automatically before it becomes a problem. We also monitor all bounces and see when we can retry prospects and know when it lands in the inbox versus the spam box. We are confident we have the best deliverability at any statistically significant volume: send 25,000 emails on one campaign through Sender Pools and the same campaign through any other tool or infrastructure, and we expect to win.

Keep them! Domains are free through us so we will never ask you to import or buy domains.

We typically aim for an even balance of Google, Microsoft and SMTP mailboxes across your account, but that is a starting point rather than a rule. As we learn who you are targeting and how your copy performs, we auto-balance toward whichever mailbox types are landing in the inbox for you. Depending on your list and your copy the mix can skew toward one provider or another, and it can shift in different directions at different times. All of that happens automatically.

Yes, we are month to month cancel anytime. We work off a credit based system as well so if you want to ramp up or ramp down at any point we're built for that!

As many as it takes. Sender Pools sizes your pool to deliver the contacts you upload inside the auto-quoted window of about 30 days, builds roughly 50% more mailboxes and domains than that requires as a buffer, and replaces any that get burned. There is no per-mailbox charge, so the count is an engineering decision rather than a billing one.

Google Workspace, Microsoft 365 and SMTP mailboxes. We typically aim for an even balance of the three, but that is a starting point rather than a rule. As we learn who you are targeting and how your copy performs, the mix auto-balances toward whichever provider is landing in the inbox for you. Depending on your list and your copy it can skew toward one provider or another, and it can shift in different directions at different times.

It is replaced automatically at no cost. Sender Pools monitors every mailbox, and when performance dips or a domain lands on a blocklist, the mailbox is rotated out and a warmed replacement takes over. The fair use policy covers replacing up to 50% of your mailboxes and domains every month.

No. Warmup is continuous. Every mailbox is warmed before it starts sending and keeps exchanging warmup traffic for as long as it is live, so reputation is maintained rather than spent.

Yes. Every domain Sender Pools buys is authenticated and configured before its mailboxes start warming. You do not touch DNS.

No. Sender Pools sends from secondary domains it buys for you, so your primary domain's reputation is never used for cold outreach. You keep your existing domains for normal business email.

Across the network over the trailing 30 days: 97.4% inbox placement, 1.4× the reply rate of the same lists on legacy tools, and more than 1,000,000 emails a day sent. Individual results depend on list quality and targeting.

We are confident it is, at any volume large enough to be statistically significant. Send 25,000 emails on one campaign through Sender Pools and the same campaign, list and copy through any other cold email tool or infrastructure, and we expect Sender Pools to win on inbox placement and replies. Small tests can go either way because a handful of mailboxes or a single bad domain can swing the result; at scale, the auto-balancing, monitoring and rotation described above are what make the difference.

By doing the maintenance automatically instead of reporting it. Sender Pools auto-balances sends across mailboxes and providers, runs blacklist checks, tracks bounces to decide when a prospect can be retried, distinguishes inbox placement from spam placement, keeps warming live mailboxes, and rotates out any mailbox whose performance dips before it affects your results.

Yes. Every recipient is checked before a single send goes out, and verification credits are included in every plan at three times the send count.

It can. Sender Pools writes a first and second touch for each person based on your ICP, times each message to the recipient's most likely reading time, and lets you preview generated copy against a real prospect before it sends. You can also supply your own templates and run multiple variants on a step as a random-split A/B test.

Into a merged inbox that collects every reply from every mailbox in one place. Replies are classified so you can filter by interested, unread, out-of-office or archived, and you can reply or forward from the mailbox that sent the original.

Smartlead and Instantly are sequencers: you pay a software subscription and then buy domains and mailboxes separately, warm them, and replace them when they burn. Sender Pools charges one per-send price that includes the domains, the mailboxes, warmup, rotation, verification, AI copy and the inbox. As volume grows, the per-mailbox model gets more expensive while Sender Pools' per-send rate steps down.

Yes. Sender Pools replaces both the sequencer and the infrastructure you would otherwise buy alongside it. The pricing page has a side-by-side cost comparison at your volume, and the blog has a detailed breakdown of what each tool charges for.

No. Sender Pools buys the domains and creates the Google, Microsoft and SMTP mailboxes for you at no charge. There is nothing to import, connect or renew.

Yes. The public REST API is documented at https://sender-pools.readme.io and authenticates with a bearer API key. It covers workspaces, ICPs, contacts, sequences and copy, the inbox, mailboxes, do-not-contact lists and webhooks.

The Sender Pools MCP server lets an AI agent such as Claude, Cursor or Claude Code operate your account in plain English. It exposes 52 tools covering everything in the product: import lists, create and schedule ICPs, write and A/B test copy, triage the inbox, watch mailbox health and manage webhooks. It runs over Streamable HTTP at https://api.senderpools.com/api/mcp, so there is nothing to install locally. Setup instructions are at https://senderpools.com/mcp.

Create an API key in your Sender Pools account, then add the server to your MCP client with the URL https://api.senderpools.com/api/mcp and an Authorization header of "Bearer <your API key>". In Claude Code that is one command: claude mcp add --transport http sender-pools https://api.senderpools.com/api/mcp --header "Authorization: Bearer <your API key>". Ask the agent "who am I authenticated as?" to confirm.

Only the account the API key belongs to. No tool takes an account id, so an agent cannot reach another customer's data. Read tools accept the literal workspace id "all" to span every workspace in the account; write tools are pinned to a single workspace so nothing bulk-edits by accident.

Any client that speaks Streamable HTTP MCP, including Claude Desktop, Claude Code and Cursor. The server exposes tools only, with no resources or prompts.

Share your unique referral link from your Sender Pools account. When a friend creates an account through it, 1,000 credits land in their balance and 1,000 in yours, immediately and automatically. Referrals are uncapped and the credits never expire. Details at https://senderpools.com/refer.

One credit is one email sent from your pool. Domains, mailboxes, warmup and verification are already free, so credits only ever pay for sends that go out.

The moment your friend finishes creating their account. 1,000 go into their balance and 1,000 into yours, no waiting for a first campaign or payment.

No. Refer ten people, earn ten times the credits. The only rule is one reward per new, real account.

Your link carries a unique code. When someone opens it we remember the referral in their browser, and when they sign up we tie the new account to yours. You can watch every step in your referral dashboard.

Never. They sit in your balance until you spend them and stack with any credits you buy.

A second account for the same person or company is not a referral and will not be credited. Referring a colleague at a different company is fair game.