The Cheapest Way to Send Cold Emails at Scale: Where the Cost Curve Bends
At published prices, 10,000 sends a month costs $38 on the Growth plan. At 100,000 sends it costs $198 on Business. The software line item rises steadily, but above roughly 10,000 sends the real constraint becomes how many mailboxes and SMTP slots you can keep healthy.
Updated October 29, 2026
Ten thousand sends: the software bill is the whole bill
At 10,000 sends a month the software decision is simple. The Growth plan on this site is $38/month and covers 10,000 emails, a reply inbox and API keys. Nothing about volume forces a second purchase yet. One person can watch the reply inbox and adjust sequences without extra tooling.
The trap is buying more than the volume needs. A reader sending 10,000 emails a month does not need five SMTP slots or bulk campaign tooling. Paying for headroom you will not use for a year is the most common way to overspend at this stage. Match the plan to the sends you actually queue, then revisit when the number moves.
- Count real sends per month, not contacts in the list
- Check whether the plan includes a reply inbox before adding a second tool
- Keep one sender setup until volume forces a split
- Re-price the plan the month your queued sends cross the tier
If the monthly figure still feels high, compare plans oncheap cold email softwarebefore adding any second subscription.
Ten thousand to fifty thousand: slots start to matter
Between 10,000 and 50,000 sends the plan price is no longer the interesting number. The Scale plan is $78/month for 50,000 emails, bulk campaigns and mailbox health. That is a modest step up, but it assumes the mailboxes behind it can absorb the volume without complaint.
This is where buyers discover that a single sending identity has a practical ceiling. If you spread 40,000 sends across one mailbox, the per-mailbox load is high. Adding mailboxes costs money separately, whether through a hosting product or an SMTP provider. The plan price and the mailbox cost have to be read together.
- Divide monthly sends by the number of mailboxes you actually control
- Price a spare mailbox before you need it, not after
- Treat mailbox health tooling as part of the cost, not a bonus
- Recheck the arithmetic whenever you add a domain
Where slots are included in the plan,cold email software with SMTPis the simpler purchase because the mailbox and the sender arrive together.
One hundred thousand sends: mailbox count sets the bill
At 100,000 sends a month the Business plan is $198/month and includes two SMTP slots. That is the published figure for the software. The honest question is whether two slots carry 100,000 sends in a way you are comfortable with, or whether you need more mailboxes than the plan provides.
Here the cost curve stops being about plans. If you need additional verified SMTP accounts, LocalSMTP sells five for a one-time $149. Five accounts plus the two included slots is seven sending identities, purchased once rather than rented monthly. Do the division yourself: 100,000 sends across seven mailboxes is a very different load per mailbox than across two.
- Work out sends per mailbox at your real volume
- Compare renting extra slots monthly against a one-time block
- Keep a written count of domains, mailboxes and slots you own
- Recalculate after every new domain you warm up
If you would rather own the sending layer than rent it,buy cold email softwarecovers the one-time options alongside the monthly plans.
A worked example at 100,000 sends
Suppose you queue 100,000 emails a month and want seven sending identities. The Business plan is $198/month. LocalSMTP Starter 5 is a one-time $149 for five verified SMTP accounts with lifetime access. Two $149 licences would give ten accounts, though you only need five here.
The first month costs $198 plus $149. Every month after that costs $198, because the SMTP accounts were bought once. Compare that against any arrangement where extra slots are rented monthly and the gap widens with each month you keep sending. The arithmetic is yours to run on your own volumes.
- Write the first-month total and the steady-state total separately
- Multiply the monthly figure by twelve before calling anything cheap
- Confirm whether extra slots are rented or owned
- Check the vendor's current published terms before you commit
Where the curve flattens and where it does not
Below 10,000 sends, software price dominates and the cheapest plan that fits is usually correct. Between 10,000 and 50,000, the plan price rises gently while mailbox cost begins to appear. Above 50,000, mailbox count is the line that moves, and the plan is a smaller share of the total.
Mail Pro at $149 is a lifetime unlimited licence with unlimited contacts and mailboxes and warm-up on every account. For a sender who expects to keep adding mailboxes over years, a one-time purchase changes the shape of the curve entirely. Read the terms, then decide whether ownership or rental fits how long you plan to send.
- Identify which line item grows with volume on your setup
- Prefer owned capacity when the sending will run for years
- Review the curve every quarter against actual sends
- Do not buy capacity for a volume you have not reached
Published prices that shape the cost of 10,000 to 100,000 cold emails a month
| Option | Price | What you get | Best for |
|---|---|---|---|
| Growth | $38/month | 10,000 emails a month, reply inbox, API keys | Senders at the bottom of the curve |
| Scale | $78/month | 50,000 emails a month, bulk campaigns, mailbox health | Senders whose volume is climbing |
| Business | $198/month | 100,000 emails a month, two SMTP slots, diagnostics | Senders at the top of the curve |
| LocalSMTP | $149 | Starter 5, five verified SMTP accounts with lifetime access | Adding mailboxes once instead of renting slots |
| Mail Pro | $149 | Lifetime unlimited licence, unlimited contacts and mailboxes, warm-up on every account | Long-running senders who keep adding mailboxes |
Each figure is the vendor's published price for that product alone; code SALE20 takes 15% off lifetime deals, and monthly plans are billed as listed.
What this cost curve will not tell you
These are published prices and simple division. They say nothing about whether your campaigns will perform, and they assume your volumes are real rather than aspirational.
- It cannot predict how many mailboxes your domains will support in practice
- It does not include the cost of domains, DNS or hosting beyond what is listed
- It cannot tell you whether a lifetime licence suits a business that may stop sending
- It gives no guidance on inbox placement, which no price protects
- It assumes you will not exceed the send cap on the plan you choose
Frequently asked questions
Is it cheaper to buy lifetime SMTP accounts or rent slots monthly?
Compare the one-time price against the monthly slot cost over the months you expect to send. LocalSMTP is a one-time $149 for five accounts. If you would rent extra slots for years, the owned option usually wins on arithmetic alone. Check both vendors' current terms.
What does 100,000 cold emails a month cost at published prices?
The Business plan is $198/month for 100,000 emails and two SMTP slots. If you add LocalSMTP at a one-time $149 for five more accounts, the first month is $198 plus $149 and later months are $198.
Does a higher plan remove the need for more mailboxes?
No. Plans add sends and slots, but the number of mailboxes behind those sends is a separate decision. Above roughly 10,000 sends, divide your volume by your mailbox count and judge whether the load per mailbox is one you can manage.
Can I start small and change plans later?
Yes. The monthly plans step from $18/month to $1000/month, so you can move up as queued sends grow. Nothing in the published pricing penalizes starting on the smallest plan that fits your current volume.
Run the arithmetic on your own send volume
Start with the plan that matches the sends you queue this month. The Starter plan is $18/month and the Growth plan is $38/month, both listed on the pricing page with their caps.
Compare the monthly plans