Written by the Inboxrise team. We make one of the tools on this list, and we put it first. The criteria behind the order are below, so you can judge them yourself. Every price and feature for another tool comes from that company's own pages, checked on 5 November 2026. These change, so check theirs before you buy.
The short version
All six tools below can pause sending when bounces climb. They differ in what they pause, at what rate, and whether you have to turn it on.
- Inboxrise: best if you want a slow start and bounce protection working from the first send, on each inbox, each list and each address, with nothing to turn on.
- Instantly: best when you need high sending volume at a flat monthly price.
- Smartlead: best for a flat price with unlimited email accounts, starting lower than Instantly.
- Lemlist: best if you want a lead database and multichannel outreach in one tool, and you are fine paying per user.
- Apollo: best if finding contacts is your main problem.
- Saleshandy: best for large lists: its Scale plan has no cap on prospects, under a fair usage policy.
How we ranked them
Cold email only pays while your domain can still reach the inbox. A domain that sends too much, too soon, or keeps mailing dead addresses ends up in spam, and every email after that is wasted. So we asked three questions of every tool:
- Does it protect your domain without being asked? What stops sending, at what point, and is it working from the start?
- Is every email about the person who gets it? An email that could have gone to anyone gets treated that way.
- What does it cost to start, with warmup included?
We weighted the first two most. If volume or a lead database is what you need, the order changes, and each section says when another tool is the better pick.
What each tool does when bounces climb
A bounce is an email that could not be delivered. Here is what each company's own pages said on 5 November 2026.
| Tool | What it pauses | At what point | Do you have to turn it on? |
|---|---|---|---|
| Inboxrise | The inbox, and the unsent contacts on a list | Inbox: 8% over 7 days, once it has sent 25. List: 8%, once 50 are emailed and 5 have bounced | No |
| Instantly | The campaign | Over 5%, once it has sent 200. You can change the rate | No, it is on by default, and you can turn it off |
| Smartlead | The campaign | The rate you set | Yes, in the campaign's setup |
| Lemlist | The campaign | 50%, once 100 leads are contacted, with an alert at 10% | No |
| Apollo | The sequence | The rate an admin sets. No default is published | An admin sets the thresholds |
| Saleshandy | The sequence | "Multiple bounces". No rate is published | No, it is described as automatic |
1. Inboxrise
Best for: small teams and agencies that cannot afford to burn a sending domain.
Inboxrise is cold email software with built-in warmup. Its job is to stop sending when sending would hurt your domain.
How it protects your domain
Warmup is included for every inbox. An inbox is warmed for 14 days and kept out of campaigns until day 10, unless you choose to send early, which holds it to a low daily cap. The rest works on every plan, with nothing to turn on:
- Sending ramps up. A new inbox starts at 5 emails a day and adds 5 a day, up to its own daily limit, 50 unless you change it.
- An inbox with high bounces pauses. It stops at 8% bounces over 7 days, once it has sent 25. Other inboxes keep sending.
- A bad list is held. Once 50 contacts on a list have been emailed and 5 have bounced, at 8%, its unsent contacts are held and you are told. Other lists keep sending.
- A dead address stops everywhere. An address that hard-bounces is stopped in all your campaigns.
When you verify a list, a contact whose domain has expired or whose website is dead is marked invalid and is not sent to. You can also test where a campaign lands before it goes live. These are your account's guards, so you can override them: keep an inbox active, or send a held list anyway after a warning.
What else it does differently
- Every email starts with the lead. In Target mode, each email opens with one sentence about the lead's own business, checked against their website, then a linking line you approved that ties it to your offer. Lex writes each lead's subject line from words on their site. If a fact cannot be checked, that lead gets your email exactly as you wrote it.
- Lex does the work. Lex, the AI assistant inside the app, builds campaigns with you, tests where they land, explains why a campaign is not sending, and drafts replies to prospects. Anything that changes your account waits for your confirmation.
Pricing (see Inboxrise pricing)
- Starter, $29 a month: unlimited inboxes, each warmed; 2,500 contacts; 10,000 emails a month; 5 active campaigns.
- Growth, $79 a month: 25,000 contacts, no hard email limit, Lex drafts emails and replies, Target mode with 2,500 openings a month.
- Scale, $249 a month: 100,000 contacts, Target mode with 10,000 openings a month, webhooks and API, a workspace per client.
- Annual billing saves 25%. The 14-day free trial needs no credit card and includes Target mode.
Pros
- Warmup on every inbox, at no extra cost, on every plan.
- Domain protection is part of every plan, never an add-on.
- A bad list is held on its own, so one list does not stop the rest.
- Personalisation is checked against the lead's own website, so it does not invent things about them.
Cons
- Its inbox pause starts at 8%, above Instantly's 5% default.
- No built-in lead database. You bring your own list as a CSV.
- Fewer integrations than older tools. Webhooks and the API are on Scale only.
- Target mode starts on Growth. On Starter, your emails go out as you wrote them.
- Gmail and Outlook connect with an app password, which takes a few minutes to set up.
- It is newer and smaller than the other tools on this list.
2. Instantly
Best for: high sending volume at a flat monthly price.
How it protects your domain: its high bounce auto-pause is on by default. A campaign pauses when its bounce rate goes over 5%, once it has sent at least 200 emails. You can change the rate or turn the feature off.
Pricing (billed monthly; lower with yearly billing; see Instantly pricing)
- Growth, $47 a month: 1,000 uploaded contacts, 5,000 emails a month.
- Hypergrowth, $107 a month: 25,000 contacts, 125,000 emails a month.
- Light Speed, $358 a month: 100,000 contacts, 500,000 emails a month.
- Every listed plan includes unlimited email accounts and unlimited warmup. You can start without a credit card.
Pros
- Unlimited email accounts and warmup on every listed plan.
- A bounce pause that is on by default, at a lower rate than Inboxrise's.
- One flat price, not a price per user.
- Very large email allowances on the higher plans.
Cons
- The bounce pause works per campaign and waits for 200 sends.
- The entry plan allows 1,000 uploaded contacts, so a list of a few thousand needs Hypergrowth at $107.
Pick Instantly over Inboxrise if your plan depends on sending tens of thousands of emails a month from many inboxes.
3. Smartlead
Best for: a flat price with unlimited email accounts, starting lower than Instantly.
How it protects your domain: its high bounce rate auto protection pauses a campaign at a rate you choose. You enable it in the campaign's setup.
Pricing (billed monthly, with the yearly price in brackets; see Smartlead pricing)
- Base, $39 a month ($32): 2,000 active leads, 6,000 emails a month.
- Pro, $94 a month ($78): 30,000 active leads, 90,000 emails a month.
- Unlimited Smart, $174 a month ($144): 150,000 emails a month.
- Unlimited Prime, $379 a month ($315): 500,000 emails a month.
- In Smartlead's words, all plans include "unlimited email accounts at no extra cost." Every plan has a free trial with no credit card.
Pros
- Unlimited email accounts on every plan.
- A lower entry price than Instantly.
- You choose the bounce rate that pauses a campaign.
Cons
- Bounce protection is a setting you have to enable.
- Its pricing page mentions warmup but does not say which plans include it. Check before you buy.
Pick Smartlead over Inboxrise if you want volume and a lower entry price than Instantly.
4. Lemlist
Best for: a lead database and multichannel outreach in one tool, if you are fine paying per user.
How it protects your domain: Lemlist sends a bounce alert at 10% and pauses a campaign automatically at 50%, once at least 100 leads have been contacted. Its own advice is to pause by hand if bounces spike.
Pricing (per user, billed monthly, with the yearly price in brackets; see Lemlist pricing)
- Email, $69 per user a month ($55): unlimited email senders.
- Multichannel, $109 per user a month ($87): 5 senders per user.
- Lemlist's own warmup, lemwarm, is included in all plans. Lemlist lists a lead database of more than 650 million leads; finding emails and phone numbers uses enrichment credits, with an add-on of 2,000 credits a month for $20. There is a 14-day free trial.
Pros
- A built-in lead database.
- Warmup included on every plan.
- A multichannel plan for teams that work more than email.
Cons
- The automatic pause waits for a 50% bounce rate, so you have to act on the alert yourself.
- Priced per user, so a team of three pays three times over.
- Finding contact details costs enrichment credits on top of the plan.
Pick Lemlist over Inboxrise if you need to find leads and work several channels from one tool.
5. Apollo
Best for: finding contacts. Apollo says it has more than 240 million contacts and 30 million accounts.
How it protects your domain: since July 2026, an admin can set the bounce rates that auto-pause a sequence. Apollo also blocks emailing hard-bounced addresses, and its catch-all protection is on by default.
Pricing (per seat, billed monthly, with the yearly price in brackets; see Apollo pricing)
- Free, $0: connects Gmail only. Paid plans add other email providers.
- Basic, $65 a seat a month ($49).
- Professional, $99 a seat a month ($79).
- Organization, $149 a seat a month ($119): minimum 3 seats.
- Email warmup is listed on Basic and up, and credits cover it. Credits are shared across your team, granted each billing cycle, and do not roll over.
Pros
- A very large contact database.
- Prospecting, outreach and a dialer in one product.
Cons
- The free plan works with Gmail only.
- Priced per seat, so a team pays more with each person.
- Unused credits do not carry over.
Use Apollo with Inboxrise: plenty of teams find contacts in Apollo and send from a separate tool. Export a CSV from Apollo and import it into Inboxrise.
6. Saleshandy
Best for: large lists. Its Scale plan has no cap on prospects, under a fair usage policy, at $189 a month.
How it protects your domain: Bounce Guard pauses a sequence automatically when it sees bounces, and you check the cause and resume by hand. Saleshandy does not publish the rate that triggers it.
Pricing (billed monthly, with the yearly price in brackets; see Saleshandy pricing)
- Starter, $41 a month ($34): 2,000 active prospects, 6,000 emails a month.
- Pro, $99 a month ($76): 30,000 prospects, 100,000 emails a month.
- Scale, $189 a month ($149): unlimited prospects under a fair usage policy, 200,000 emails a month.
- Unlimited email accounts and unlimited warmup on every plan, with a daily warmup limit that depends on the plan. There is a 7-day free trial.
Pros
- Unlimited email accounts and warmup.
- An automatic bounce pause.
- No prospect cap on its Scale plan, for less than Instantly charges for 100,000 contacts.
Cons
- The rate that triggers the bounce pause is not published.
- The 7-day trial is the shortest on this list.
Pick Saleshandy over Inboxrise if you are working a very large list and want no cap on prospects.
Side by side
Entry plan, billed monthly, as each company's own pricing page showed it on 5 November 2026.
| Tool | Starting price | Email accounts | Warmup included | Contacts | Emails a month |
|---|---|---|---|---|---|
| Inboxrise | $29 | Unlimited | Yes, every inbox | 2,500 | 10,000 |
| Instantly | $47 | Unlimited | Yes, unlimited | 1,000 | 5,000 |
| Smartlead | $39 | Unlimited | Not stated per plan | 2,000 | 6,000 |
| Lemlist | $69 per user | Unlimited senders | Yes, lemwarm | Not stated | Not stated |
| Apollo | Free plan; Basic $65 per seat | Not stated | Basic and up, using credits | Not stated | Not stated |
| Saleshandy | $41 | Unlimited | Yes, unlimited | 2,000 | 6,000 |
Common questions
What is the best cold email software for protecting your domain?
One that starts new inboxes slowly and stops sending on its own when bounces climb, before they do lasting damage. That is what Inboxrise is built for, on every plan and with nothing to turn on. Instantly also pauses on high bounces by default. If your plan depends on very high volume from day one, look at Instantly, Smartlead or Saleshandy instead.
What bounce rate should pause a cold email campaign?
There is no single standard. Instantly pauses at 5% by default, once a campaign has sent 200 emails. Inboxrise pauses an inbox at 8% over 7 days, once it has sent 25. Lemlist alerts at 10%. Smartlead lets you choose, and its own examples use 3% and 5%. Whichever rate you use, clean the list before you resume.
Does warmup alone protect my domain?
No. Warmup builds a sending reputation, and a list full of dead addresses can still damage it. You need warmup, a slow start and a pause on bounces together. Our warmup protocol covers the schedule, and our free checker tests your SPF, DKIM and DMARC records.
Do I need to warm up a new inbox?
Yes. A new inbox has no sending reputation, and mail from it is treated with suspicion until it has one. Inboxrise warms an inbox for 14 days, and campaigns can start on day 10. Instantly, Lemlist and Saleshandy also say warmup is included on their plans, and Apollo lists it on its paid plans.
How many emails a day should a new inbox send?
Start low and build up. In Inboxrise, a new inbox starts at 5 a day and ramps up, and each inbox sends up to its own daily limit, 50 a day unless you change it.
Can I use contacts from Apollo in Inboxrise?
Yes. Export them from Apollo as a CSV and import the file into Inboxrise.
Does Inboxrise write the whole email with AI?
No, on purpose. You write the email once, or draft it with Lex. For each lead, Lex adds one sentence about their business, checked against their website, picks one of the linking lines you approved, and writes a subject from words on their site. The rest goes out exactly as you wrote it.
Why is Inboxrise first on a list written by Inboxrise?
Because we wrote it, and we ranked by what we think matters most: protecting your domain and writing to each lead. If you rank by volume or price per email instead, the order changes, and the sections above say when another tool is the better choice.
Try it
See what Inboxrise does, or start a 14-day free trial. No credit card, and Target mode is included.