Unlimited mailboxes + warmup on all plans. Best whitelabel for agencies ($29/workspace). Strongest deliverability infrastructure. Choose this if per-mailbox costs are your biggest pain point or you manage multiple client domains.
Try Smartlead Free (14 days) →Built-in 450M+ lead database, AI Sales + Reply agents, free tier for testing. Best if you want leads + sending + AI from one platform. Budget for the $194 Scale bundle — the $47 entry plan is too limited.
Try Instantly →Both tools were built for cold email outreach, but they've evolved in different directions. Smartlead has doubled down on sending infrastructure — unlimited mailboxes, best-in-class warmup, and agency-friendly architecture. Instantly has become an all-in-one outbound platform — buying leads, warming mailboxes, sending sequences, and using AI to handle replies, all under one roof.
The result is two tools that overlap significantly on core sending features but diverge sharply on what they're optimized for. Using the wrong one for your use case means either overpaying for database features you don't need (Instantly) or manually sourcing leads and stitching together a tool stack (Smartlead).
| Feature | Smartlead | Instantly | Winner |
|---|---|---|---|
| Unlimited mailboxes | ✓ All plans | ✓ All plans | Tie |
| Email warmup | ✓ Unlimited, all plans | ✓ Unlimited, all plans | Tie |
| Inbox rotation | ✓ Automatic across all | ✓ | Tie |
| Unified inbox | ✓ Master inbox, all plans | Unibox — Scale bundle+ | Smartlead |
| Conditional sequences | ✓ Subsequences on all plans | ✓ | Smartlead (subsequences) |
| A/B testing | ✓ | ✓ A/Z multi-variant | Instantly (more variants) |
| B2B lead database | SmartProspect add-on | ✓ 450M+ built-in | Instantly |
| AI writing / agents | SmartAssistant (basic) | ✓ AI Sales + Reply agents | Instantly |
| Built-in CRM | Basic (Pro+) | ✓ Full CRM (Scale bundle) | Instantly |
| Agency whitelabel | ✓ $29/workspace (Pro+) | ✗ Not available | Smartlead |
| Client workspaces | ✓ Isolated per client | ✗ | Smartlead |
| Private IP / SISR | SmartServers add-on ($39/server) | Lightspeed+ (Agency bundle) | Tie |
| API + webhooks | ✓ All plans, strong API | ✓ | Smartlead (better documented) |
| Free trial | ✓ 14 days, no card | ✓ Free tier available | Instantly (permanent free tier) |
Both tools use different pricing architectures that make direct comparison tricky — Smartlead charges by volume tier, Instantly sells outreach plans and credit plans separately.
| Plan | Price | Sends/mo | Contacts |
|---|---|---|---|
| Base | $39 | 6,000 | 2,000 |
| Pro | $94 | 90,000 | 30,000 |
| Unlimited Smart | $174 | 150,000 | Unlimited |
| Unlimited Prime | $379 | 500,000 | Unlimited |
All plans: unlimited mailboxes, unlimited warmup. Annual billing saves 17%. Agency whitelabel: +$29/workspace/month (Pro+).
| Plan | Price | What it covers |
|---|---|---|
| Outreach Growth | $47 | Unlimited accounts, 5K sends, 1K contacts — sending only |
| Outreach Hypergrowth | $97 | 100K sends, 25K contacts, Unibox |
| Credits Growth | $47 | 1,500–2,000 database credits/mo — separate from outreach |
| Bundle Scale ⭐ | $194 | Full stack: sending + leads + AI Reply + Unibox |
| Bundle Agency | $555 | 500K sends, 100K contacts, SISR |
Instantly's real entry price is $194, not $47. The $47 outreach plan excludes the lead database, AI agents, and Unibox. To get a functional full-stack product, you need the Scale bundle. Factor this into your comparison — at the growth-stage price point, Instantly ($194) is more expensive than Smartlead Pro ($94) once you account for what you actually get.
Both of these are flat-rate, so neither charges you per seat — a real advantage over Apollo and Lemlist. Drag your team size and watch the two flat lines hold while the per-seat tools climb:
Both tools have strong deliverability track records built on unlimited warmup and inbox rotation. The practical difference is in what happens when things go wrong and what visibility you have into inbox placement.
Smartlead offers SmartDelivery as an add-on — an inbox placement monitoring tool that shows you where emails are landing (inbox vs spam) across major providers, plus blacklist monitoring alerts. Instantly doesn't have an equivalent built-in tool; you'd need a third-party like GlockApps.
For most users, day-to-day deliverability performance is comparable between the two. If you're managing client accounts where deliverability SLAs matter, Smartlead's monitoring tools give you more visibility.
This is where the comparison isn't close. Smartlead was built with agencies in mind; Instantly wasn't.
| Agency need | Smartlead | Instantly |
|---|---|---|
| Isolated client workspaces | ✓ $29/workspace | ✗ |
| Whitelabel (rebrand for clients) | ✓ | ✗ |
| Master inbox across clients | ✓ | ✗ |
| Per-client reporting | ✓ | Possible but not native |
| Client access management | ✓ | ✗ |
If you're running a cold email agency with 3+ clients, Instantly is functionally unworkable — there's no way to isolate client campaigns, data, or access. Smartlead at $94/month + $29 per client workspace is the clear choice.
Instantly has the better AI story. The AI Sales Agent can draft initial outreach, and the AI Reply Agent can handle objections and move conversations forward automatically — reducing the manual work of reply management for teams without full SDR coverage. These are available on the Scale bundle and above.
Smartlead's SmartAssistant provides AI-assisted writing in sequences, but it's more of a copywriting aid than a true autonomous agent. The gap between the two on AI is real, but worth framing correctly: Instantly's AI Reply Agent does real work; Smartlead's API and Clay integration let you build more customized AI workflows if you need them.
Choose Smartlead if: You manage 3+ client accounts. You send 500+ emails/day across multiple domains. Per-mailbox costs are your biggest pain. You want to build on a strong API with Clay or n8n. You need agency whitelabel. Try Smartlead free →
Choose Instantly if: You want leads + sending + AI from one platform. You're a solo founder or small team without a separate lead sourcing workflow. You want a free tier to test before committing. You value AI reply management. Budget for the $194 Scale bundle. Try Instantly →
Some teams use Instantly's Credits plan ($47/mo) as their lead database and Smartlead for sending — getting the 450M+ database quality at low cost while keeping Smartlead's infrastructure for outreach. This adds a CSV export/import step but separates the two functions cleanly.
Written by
Scott Holmes
AI systems consultant and cold email infrastructure specialist. Founder of Pinnacle Tech Projects. All pricing verified against live product pages July 2026.