Smartlead Unibox: How to Manage All Replies in One Inbox

Smartlead Unibox is the shared reply inbox inside Smartlead, now called the Unified Master Inbox, that pulls every response from every connected mailbox into one login. It sorts replies into lead categories, lets a team filter, assign and bulk-action conversations, and pushes interested leads to a CRM or Slack. This guide shows how to set it up and run it daily.

Last updated: October 2026. Prices checked against Smartlead’s official pricing page.

What is Smartlead Unibox?

Smartlead Unibox is a unified reply inbox that collects responses from all mailboxes connected to your Smartlead account and shows them in one view. Smartlead’s help center calls it the Master Inbox, the product page calls it the Unified Master Inbox, and older tutorial videos still use the Unibox name.

Cold email teams spread sending across many inboxes, and Smartlead allows unlimited email accounts on every plan, so twenty mailboxes means twenty places a reply can land. Without a central inbox, hot replies sit unanswered. For a full product verdict beyond the inbox, see our hands-on Smartlead review.

In short, Unibox is the reply layer of Smartlead: one inbox for every sending account.

Where to find the Master Inbox and what it shows

The Master Inbox is the reply workspace you open from Smartlead’s left navigation, separate from the Campaigns and Email Accounts screens. It lists inbound replies across all campaigns, and each conversation can be filtered by the campaign it came from, the sending mailbox and the lead category assigned to it.

Source: Smartlead Unified Inbox product page (smartlead.ai/unified-inbox), checked October 2026.

The table shows the real gain: Unibox removes the manual sorting and context-hunting around each reply.

How does Smartlead Unibox sort replies?

Smartlead Unibox sorts replies with lead categories, which are labels attached to each lead based on what the reply means. Categories drive almost everything else in the inbox: saved views, CRM syncs, client visibility and follow-up subsequences all filter on them, so a clean category setup is the foundation of the workflow.

Smartlead’s API documentation lists five default categories, and you can add custom ones in Settings:

• Interested: A lead who signals intent to talk or buy. This is the category most teams sync to a CRM deal stage and route to the fastest responder.
• Meeting Request: A reply asking for a call or proposing a time slot. Teams usually answer these first because the lead has already accepted the next step.
• Not Interested: A clear decline. Keeping these labelled stops accidental re-contact and gives an honest view of how a message lands with a segment.
• Do Not Contact: An explicit request to stop emailing. This category protects compliance and sender reputation, so these leads should never return to a campaign.
• Information Request: A lead asking for pricing, a case study or details before deciding. These replies often convert with a short, specific answer and one asset.

The inbox also auto-detects and tags out-of-office, bounce and unsubscribe replies so they do not clutter the feed. Set categories up first, and every filter, view and integration becomes more useful.

How to turn on AI reply categorization

AI reply categorization is a campaign setting that lets Smartlead read each reply and assign a lead category automatically instead of a person tagging it. It lives in each campaign’s Settings tab, in the AI and Automation section, where you choose between SmartLead AI auto-categorization and a Manual Only mode.

1. Open the campaign and go to the Settings tab.
2. Find the AI and Automation section.
3. Choose SmartLead AI to auto-categorize replies, or Manual Only if people should tag every reply.
4. Select which lead categories the AI is allowed to assign.
5. Optionally add a custom prompt that explains how your team defines an interested lead.
6. Save and launch, then spot-check the first categorized replies in the Master Inbox.

Treat AI tagging as a first pass and correct borderline replies like “maybe later” by hand during the first week.

How do saved Views work in the Master Inbox?

A saved View is a stored filter combination in the Master Inbox that shows only the replies matching chosen criteria. Views turn one crowded feed into focused queues, such as Interested replies for one client this week, and a View can be made public so the whole team works from the same queue.

Smartlead’s help center lists eight filters a View can combine; these five do most of the work:

• Lead Category: Filters replies by label such as Interested or Information Request. Most teams build their main working queue on this filter alone.
• Email Campaign: Limits the feed to one or more campaigns. Useful when different people own different offers or when a launch needs close monitoring.
• Sender Email Account: Shows replies that reached one specific mailbox. Handy for diagnosing a domain that suddenly gets odd responses or bounce notices.
• Client: Shows only replies that belong to one client workspace. Agencies use this to give each account manager a clean, separate queue.
• Team Member: Filters by the person a conversation is assigned to, so every rep can open a personal queue of open threads each morning.

The other three are Email Status, Campaign Tag and Reply Date Range. The help article also mentions View limits per plan, but it uses legacy plan names, so check your own account first.

Bulk actions and filters for high-volume days

Bulk actions are inbox operations that apply to many selected replies at once instead of one thread at a time. They matter after a large send, when out-of-office notices and short declines arrive together and need to be cleared before the real conversations get buried.

Smartlead’s unified inbox page lists five bulk actions:

• Bulk tag: Applies the same category or tag to many replies in one step, which is the fastest way to clean up after an auto-categorization miss.
• Bulk assign: Hands a group of conversations to one teammate, for example every Information Request reply from a campaign to the person who owns pricing.
• Bulk archive: Removes handled or irrelevant threads from the active view, keeping the working queue short enough to finish within one session.
• Bulk reply: Sends a response to several selected leads at once. Best kept for genuinely identical situations, since generic replies to warm leads cost meetings.
• Bulk forward: Passes a set of replies to another address, such as a client contact or a manager who needs to review a batch of objections.

Filter first, then bulk-act: that order keeps the inbox clean without archiving a lead who said yes.

How do you reply to leads from the Master Inbox?

Replying from the Master Inbox means answering a lead directly inside Smartlead, from the same mailbox that sent the original email, without opening Gmail or Outlook. The reply stays in the thread, so the lead sees a normal conversation and your team sees the full history in one place.

Saved templates handle common answers, and a Generate Reply option drafts a response with AI; Smartlead’s help article says it uses your own GPT-4 key added in profile settings, so confirm that in your account. SmartDialer users can also call a lead from the inbox.

Whatever you use, edit before sending: quote the lead’s question, answer it in two or three lines and propose one next step.

Team assignment and internal comments

Team assignment is the Master Inbox feature that gives each reply a single owner, while internal comments are notes on a thread that only your team can see. Together they stop two common failures: two reps answering the same lead, and a handoff where the closer has no idea what was promised.

A practical setup is to assign by category: Interested and Meeting Request replies go to the closer, and comments carry context such as “asked for case study, sent Tuesday”.

One owner per reply plus logged context means handoffs stop leaking leads.

How does Smartlead Unibox work for agencies and clients?

For agencies, Smartlead Unibox is a client-aware inbox: each client workspace has its own replies, and the agency decides which reply categories a client can see in their own Master Inbox. Smartlead describes the inbox as usable across clients with client dashboards, and the client-facing version can be white-labeled.

The agency setup includes five pieces:

• Client workspaces: Separate spaces per client, sold as a $29 per month add-on per workspace from Pro upward, with three included on Unlimited Prime.
• Category visibility: When adding a client, the agency chooses which reply categories to hide or show in that client’s Master Inbox view.
• Reply-only access: A restricted client login option that shows replies only, for example just Interested leads, without exposing campaigns or settings.
• Assigned mailboxes and campaigns: Clients see only the email accounts and campaigns assigned to them, so one client never sees another client’s data.
• White-label branding: Available on Pro and higher after a support request and DNS setup, so clients log in on the agency’s own subdomain.

Our guide to Smartlead white-label and client management covers the full workspace setup. For agencies, the inbox doubles as a client reporting surface.

What can you connect to the Smartlead inbox?

Smartlead’s inbox connects to outside tools through native integrations, Slack alerts, Google Sheets sync and webhooks, so a reply does not have to stay inside Smartlead to be acted on. The product page says replies can be pushed to a CRM with thread context, which keeps sales history where reps already work.

Five connection options are documented by Smartlead:

• HubSpot sync: Creates deals automatically by lead category at a chosen stage and logs sent and replied emails as activities, once enabled per campaign at lead import.
• Slack notifications: Posts real-time reply and lead alerts into a Slack channel, which suits teams that live in Slack rather than in Smartlead.
• Google Sheets sync: Copies reply data into a spreadsheet for lightweight reporting or for clients who prefer a shared sheet over a software login.
• Webhooks: Sends a JSON payload to an endpoint when chosen events fire, letting a developer route replies into any internal system or automation.
• Other native CRMs: Smartlead’s integrations page lists Salesforce, Pipedrive, Attio, Zoho CRM and GoHighLevel among its native connections for pipeline sync.

CRM access, API and webhooks start on Pro, not Base. Setup details are in our Smartlead integrations guide for HubSpot, Clay and Zapier.

Which Smartlead plan do you need for Unibox features?

Every Smartlead plan includes the Master Inbox, because the inbox is part of the core product rather than an add-on. What changes by plan is the surrounding access: CRM sync, API and webhooks, and client workspaces start on Pro, while Unlimited Prime bundles client workspaces and a dedicated manager.

Source: Smartlead pricing page (smartlead.ai/pricing), checked October 2026.

The table shows that Base works for a solo sender who answers replies inside Smartlead, while anyone syncing replies to a CRM or managing clients needs Pro or higher.

Every plan includes unlimited email accounts, so adding mailboxes never raises the bill. For the full plan math, see our Smartlead pricing breakdown.

A daily reply-handling routine that works

A reply-handling routine is a fixed order of inbox tasks that a team repeats each day so hot leads are answered first and noise is cleared fast. The routine below uses only documented Master Inbox features: Views, categories, bulk actions, assignment and comments, in an order that keeps response time low.

1. Open the Meeting Request View and answer every thread, proposing a time or sending a booking link.
2. Open the Interested View, reply with one specific next step, and assign closers where needed.
3. Clear Information Request replies with a short answer and one relevant asset.
4. Filter auto-tagged out-of-office, bounce and unsubscribe replies and bulk archive what needs no action.
5. Correct wrong AI categories so CRM sync and subsequences fire correctly.

If your sequence is still being built, our guide to building a cold email sequence in Smartlead shows how subsequences can react to these categories automatically. The routine works because it orders replies by intent, not arrival time.

Bottom line: is Smartlead Unibox worth using?

Smartlead Unibox is worth using for any team sending from more than a handful of mailboxes, because it turns scattered replies into one categorized, filterable queue with CRM and Slack hand-offs. It is included on every plan, so the real question is not cost but whether you set up categories and Views properly.

“the processing of email to organize it according to specified criteria”

Source: Wikipedia, Email filtering

That is what a reply inbox should do for a sales team. Competitors treat it as core too; Instantly markets its own version this way:

“Manage and reply to leads with AI reply labels”

Source: Instantly, Cold Email Outreach

“A shared reply inbox is only as good as its categories; set those first and the rest of Smartlead falls into place.”

Source: GrowthStackKit, Smartlead Review

The limits: AI categorization needs early supervision, and CRM, API and client features need Pro or higher. New to the platform? Start with our Smartlead setup guide, then come back to the inbox once the first campaign is live.

Verdict: set up categories, build one View per person, connect your CRM, and the Master Inbox becomes the most-used screen in Smartlead.

Frequently asked questions

The 12 most-asked questions about Smartlead Unibox.

Is Smartlead Unibox the same as the Master Inbox?

Yes. Unibox is the older name used in Smartlead tutorial videos. The help center now calls the same feature the Master Inbox, and the product page calls it the Unified Master Inbox. All three names refer to the single inbox that collects replies from every connected sending account.

Does Smartlead Unibox cost extra?

No. The Master Inbox is part of the core product on every plan, from Base at $39 per month upward. Related features depend on plan: CRM access, API and webhooks start on Pro, and client workspaces cost $29 per month each from Pro up.

How many mailboxes can feed into the Master Inbox?

Smartlead includes unlimited email accounts on every plan, and replies from all connected accounts appear in the Master Inbox. Adding more Google, Outlook or SMTP mailboxes adds no per-mailbox fee, so the inbox scales with your sending setup as it grows.

What are the default lead categories in Smartlead?

Smartlead’s API documentation lists Interested, Meeting Request, Not Interested, Do Not Contact and Information Request as default categories, and you can add custom categories in Settings. The inbox also auto-detects out-of-office, bounce and unsubscribe replies and tags them separately for quick cleanup.

Can Smartlead categorize replies automatically?

Yes. In each campaign’s Settings tab, the AI and Automation section lets you choose SmartLead AI auto-categorization or Manual Only. You pick the allowed categories and can add a custom prompt. Review the AI labels by hand during the first week.

Can I reply to leads without opening Gmail or Outlook?

Yes. You reply directly from the Master Inbox, and the message goes out from the same mailbox that sent the original email, so the thread stays intact. Templates and an AI Generate Reply option can draft responses, but edit them before sending.

Can clients see replies in Smartlead Unibox?

Yes, through client workspaces. When an agency adds a client, it chooses which reply categories that client can see, and it can grant reply-only access that shows, for example, only Interested leads. Clients only see campaigns and mailboxes assigned to them.

Does the Master Inbox sync replies to HubSpot?

Yes, on Pro and higher. The HubSpot integration can create deals by lead category at a chosen stage and logs sent and replied emails as activities. Sync must be switched on per campaign during lead import and cannot be added mid-campaign.

Can I get Slack alerts for new replies?

Yes. Smartlead’s Slack integration sends real-time notifications for replies and leads to a Slack channel. It suits teams that watch Slack all day and want to jump on Interested or Meeting Request replies without keeping Smartlead open in a browser tab.

What are saved Views in the Master Inbox?

Views are saved filter combinations. You can filter by lead category, campaign, email status, sender account, campaign tag, client, team member and reply date range, then save the combination and make it public so teammates can open the same queue each day.

Is Smartlead Unibox useful for a solo founder?

Yes, if you send from several mailboxes. Even one person running a few domains saves time by reading every reply in one feed with the campaign attached. A solo founder on the Base plan can handle replies fully inside Smartlead without CRM sync.

Can I call a lead from the Master Inbox?

Smartlead documents calling a lead directly from the Master Inbox for SmartDialer users. SmartDialer is a separate credit-based add-on that starts at $9 per month, so this option only applies if your team uses the dialer alongside email outreach campaigns.