Campaigns
A campaign is a sequence of emails sent to a set of leads, on a schedule, from a pool of mailboxes.
Building a campaign
Create the campaign
Give it a name. It starts in Draft — nothing sends until you explicitly set it Active.
Write the sequence
Add steps in order. Each step has a subject, a body, and a delay in hours after the previous step. Subject and body can use the variables below.
The body is written in a rich editor: bold, italic, underline, links, lists and images. Images go inside the email (inline), up to 1 MB each. A step with no formatting is sent as a plain-text email (unless the campaign tracks opens, which needs an HTML version).
To insert a variable, type {{ to open the variable picker, or use the Variables button. Both
work in the subject too.
You can also attach files to a step. See Step attachments.
Template variables
Write them in double braces, spelled exactly as below. They are case-sensitive. A misspelt variable
is not replaced: it is sent as written, so {{sender_signature}} or {{Signature}} would reach
the lead as literal text.
| Variable | Filled with |
|---|---|
{{firstName}}, {{lastName}}, {{email}} | The lead’s name and email |
{{companyName}}, {{companyDomain}}, {{jobTitle}} | The lead’s company and role |
{{phoneNumber}}, {{timezone}} | The lead’s phone and timezone |
{{yourCustomField}} | Any custom field on the lead, by its exact name |
{{senderName}} | The sender name of the mailbox this lead is assigned to |
{{signature}} | The signature of the mailbox this lead is assigned to |
- A lead field that is empty for a lead becomes empty text, not the raw
{{token}}. - Signature: put
{{signature}}where you want it, and it goes exactly there (plain-text or HTML signature, each part of the email gets the right form). A step without{{signature}}still gets the signature, added at the bottom automatically. It is never added twice. If the mailbox has no signature, the variable’s line is removed cleanly. - Every lead is sent from its own assigned mailbox, so
{{senderName}}and{{signature}}are that mailbox’s, not one global value.
You can create A/B variants of a step by giving two steps the same step order and a shared
variantGroup label — Sendbox alternates between them.
Before going live, run the spam-trigger-word check — it scans every step’s subject and body for common spam-filter trigger phrases.
Configure the send window
Set the hours of the day and days of the week the campaign is allowed to send. Sends outside that window queue for the next valid window rather than going out immediately.
In Settings → Sending schedule you can also set:
- Start date: nothing is sent before this moment, even when the campaign is active. It is picked in your computer’s time. Clear it to start as soon as the campaign is active.
- New leads per day: at most this many leads get their first email each day. Follow-ups are not limited by it. Blank means no limit beyond the mailboxes’ own daily caps.
Choose the mailbox pool
By default a campaign can use any workspace mailbox. You can instead configure an explicit pool:
- Manual — pick specific mailboxes.
- By tag — every mailbox with a given tag.
- Random — a random sample of N mailboxes, optionally filtered by tag.
Add leads
Add leads to the campaign. Each lead is assigned a mailbox from the pool automatically — this assignment is sticky: once a lead has a mailbox, it never changes, even if you add it again later. A lead that couldn’t be assigned (no eligible mailbox yet, or blocked by a Secure Email Gateway) is still added, unassigned, so you can see and retry it rather than having it silently disappear.
Go Active
Flip the campaign to Active. It now sends according to the send window, using each lead’s assigned mailbox.
Step attachments
Attach files to a sequence step. They are sent with every lead’s email for that step, and with test sends.
- A step’s files and images can be 10 MB in all.
- An image placed in the body is sent only while the body shows it. Remove it from the body and it is no longer sent.
- Duplicating a campaign copies its attachments.
Attachments on a first cold email hurt inbox placement. Spam filters treat files from an unknown sender as a risk. Prefer a link in the first email, and keep files for later steps or replies.
Campaign stats
Campaign numbers are counted the same way everywhere: the campaigns list, the campaign page, the CSV reports and the analytics overview.
| Number | Counts | Rate is over |
|---|---|---|
| Sent | Emails (a 3-step sequence sends 3 per lead) | |
| Leads emailed | Leads who got at least one email | |
| Opened, Clicked, Replied, Positive | Leads, each counted once | Leads emailed |
| Bounced | Emails | Emails sent |
When a campaign does not track opens or clicks, those numbers are shown blank instead of 0.
Deleting a campaign
An owner or admin can delete any campaign, one or several at a time. Before anything is deleted, the dialog shows what goes.
- Also delete N leads (on by default) deletes the leads that are in no other campaign, with their replies. Leads that are also in another campaign are kept. Untick it to keep every lead.
- Sent emails are kept. They still count for each mailbox’s daily limit, your plan’s quota and bounce health.
- Addresses on your suppression list stay blocked.
This cannot be undone. To stop a campaign but keep its history, archive it instead.
Copy fatigue
If enabled in a campaign’s settings, Sendbox watches for steps whose reply/open performance is declining over repeated sends and flags them with a suggested rewrite. You choose whether to apply the suggestion (which requires an explicit edit to the step — it’s never rewritten automatically) or dismiss the flag.
SEG handling
Leads behind a detected Secure Email Gateway (corporate mail-filtering infrastructure) can be configured to be skipped automatically rather than attempted.
The CRM view
CRM is a lightweight pipeline view of every lead who has actually replied to a campaign, grouped by sequence stage — not a list of everyone you’ve ever emailed. Use it to see who’s actually in a live conversation.