Smartlead API Reference
Authentication
All requests use query parameter auth: ?api_key={SMARTLEAD_API_KEY}
Environment variable: $SMARTLEAD_API_KEY
Base URL: https://server.smartlead.ai/api/v1
Rate Limiting
- Standard plan: 2,000 req/min (33 req/sec)
- Higher plans: 3,000 req/min (50 req/sec)
- Retry on 429 and 5xx with exponential backoff
- For bulk operations, use
p-limitorPQueuewith 8-15 concurrency
CLI Quick Reference
The smartlead CLI (@smartlead/cli) wraps all API endpoints. Use it for quick lookups:
bash# Campaigns smartlead campaigns list smartlead campaigns get <id> smartlead campaigns create --name "Campaign Name" # Leads smartlead leads list --campaign-id <id> smartlead leads add --campaign-id <id> --file leads.csv # Email accounts smartlead email-accounts list smartlead email-accounts get <id> # Analytics smartlead analytics campaign <id> smartlead analytics overall # Master inbox smartlead inbox replies
API Endpoints
Campaigns
GET /campaigns/{id} — Fetch campaign by ID POST /campaigns/create — Create new campaign POST /campaigns/{id}/status — Update status (START, PAUSED, STOP) Body: { "status": "START" }
Campaign Email Accounts
GET /campaigns/{id}/email-accounts — List accounts assigned to campaign POST /campaigns/{id}/email-accounts — Add accounts to campaign Body: { "email_account_ids": [1, 2, 3] } DELETE /campaigns/{id}/email-accounts — Remove accounts from campaign
Campaign Sequences
GET /campaigns/{id}/sequences — Fetch sequences POST /campaigns/{id}/sequences — Save/update sequences Body: { "sequences": [{ "seq_number": 1, "seq_delay_details": { "delay_in_days": 0 }, "subject": "...", "email_body": "..." }] }
A/B/C Variants — use seq_variants array inside each sequence:
json{ "sequences": [{ "seq_number": 1, "seq_delay_details": { "delay_in_days": 0 }, "seq_variants": [ { "variant_label": "A", "subject": "Subject A", "email_body": "<div>Body A</div>" }, { "variant_label": "B", "subject": "Subject B", "email_body": "<div>Body B</div>" }, { "variant_label": "C", "subject": "Subject C", "email_body": "<div>Body C</div>" } ] }] }
Note: Do NOT include distribution field — SmartLead splits evenly automatically.
Email body order: content → PS unsub line → %signature% (signature always last)
Campaign Settings & Schedule
POST /campaigns/{id}/settings — Update settings Body: { "track_settings": [...], "stop_lead_settings": "..." } POST /campaigns/{id}/schedule — Update schedule Body: { "timezone": "US/Eastern", "days_of_the_week": [1,2,3,4,5], "start_hour": "08:00", "end_hour": "17:00", "min_time_btw_emails": 8, "max_new_leads_per_day": 30 }
Leads
GET /leads/?api_key={key}&email={email} — Lookup lead by email address POST /campaigns/{id}/leads — Add leads to campaign (batch up to 100) Body: { "lead_list": [{ "email": "...", "first_name": "...", "last_name": "...", "company_name": "...", "custom_fields": { "field1": "value1" } }] }
Analytics
GET /analytics/day-wise-overall-stats ?api_key={key}&start_date=YYYY-MM-DD&end_date=YYYY-MM-DD — Day-by-day metrics (sent, opened, clicked, replied, bounced) GET /analytics/day-wise-positive-reply-stats ?api_key={key}&start_date=YYYY-MM-DD&end_date=YYYY-MM-DD — Day-by-day positive reply counts GET /analytics/overall-stats-v2 ?api_key={key}&start_date=YYYY-MM-DD&end_date=YYYY-MM-DD — Overall campaign metrics for date range GET /analytics/campaign/list ?api_key={key} — List all campaigns with summary stats GET /campaigns/{id}/analytics ?api_key={key} — Analytics for specific campaign GET /campaigns/{id}/analytics-by-date ?api_key={key}&start_date=YYYY-MM-DD&end_date=YYYY-MM-DD — Campaign analytics for specific date range (sent_count, reply_count)
Email Accounts (Global)
GET /email-accounts ?api_key={key}&offset=0&limit=100 — List all email accounts (paginated) GET /email-accounts/{id} ?api_key={key} — Get specific email account POST /email-accounts/save — Create/update email account (SMTP details, warmup, etc.)
Master Inbox
POST /master-inbox/inbox-replies Body: { "api_key": "...", "offset": 0, "limit": 50, "message_type": "RECEIVED" } — Fetch inbox replies with filtering and pagination
Sub-Client / Custom API Key Pattern
- Normal sub-clients: Pass
?api_key={MAIN_KEY}&client_id={CLIENT_ID}on all requests - Custom API key clients: Use the client's own API key directly, no
client_idparam
TypeScript Pattern
typescriptconst SMARTLEAD_API = "https://server.smartlead.ai/api/v1"; const API_KEY = process.env.SMARTLEAD_API_KEY; // GET example const res = await fetch(`${SMARTLEAD_API}/campaigns/${campaignId}?api_key=${API_KEY}`); const campaign = await res.json(); // POST example (add leads) const res = await fetch(`${SMARTLEAD_API}/campaigns/${campaignId}/leads?api_key=${API_KEY}`, { method: "POST", headers: { "Content-Type": "application/json" }, body: JSON.stringify({ lead_list: leads.slice(0, 100) }), });
Performance tip: cache the email-accounts list
If you hit /email-accounts more than a few times per script, paginate once at the start and keep the result in memory. Smartlead's pagination returns 100 per page — for accounts with thousands of inboxes, a full walk takes 30+ seconds.
For persistent caching across scripts, write the list to a local JSON file and refresh on a timer (e.g. every hour). The /smartlead-inbox-manager skill has scripts that implement this pattern.
What to do next
This is a reference skill — no direct next step. Used by all skills that interact with Smartlead (/smartlead-inbox-manager, /smartlead-campaign-upload-public, /email-deliverability-audit, /positive-reply-scoring, /deliverability-incident-response, etc.).
Return to the skill that sent you here.
Related skills
- Every skill that touches Smartlead uses this reference.
