Documentation

Sending Limits & Retry Policy

Important
Rate Limits

Understand email provider limits, Laneful's retry policies, and how to plan your email volume to avoid delivery delays.

Provider Limits Apply

All email providers have rate limits

3-Day Retry Policy

Automatic retry for failed deliveries

Important
Rate Limits

Overview

Whether you're using Relay Lanes or IP Lanes, sending limits affect how quickly your emails can be delivered. Laneful automatically handles retries and queueing, but understanding the limits helps you plan better.

How Laneful Handles Limits

Automatic Queueing: When a provider hits its limit, Laneful queues your emails and sends them as capacity becomes available.

Smart Retry: If any SMTP relay rejects messages due to rate limits or temporary errors, Laneful retries delivery for up to 3 days.

Failover: In tracks with multiple lanes, traffic automatically shifts to available lanes when others reach capacity.

Provider-Specific Limits

Each email provider has different limits. Here's what you need to know:

Gmail Limits

Personal Gmail

  • 500 emails per day
  • • Resets at midnight Pacific Time
  • • Includes all emails sent from account
  • • Temporary suspensions possible if exceeded

Google Workspace

  • 2,000 emails per day
  • • Higher limits available with SMTP Relay
  • • Better reputation and deliverability
  • • More suitable for business use
Important: Gmail's limits apply to your entire account, not just emails sent through Laneful.

SendGrid Limits

Note about Other Providers

  • • Each provider has different limits
  • • Laneful charges $5/month for any relay lane
  • • Provider fees are separate and additional

Paid Plans

  • • 40K+ emails per month
  • • Rate limits based on plan
  • • Enterprise plans available

AWS SES Limits

Sandbox Mode

  • • 200 emails per 24 hours
  • • 1 email per second
  • • Only verified emails
  • • Must request production access

Production Mode

  • • Starts at 200 emails/day
  • • Automatically increases with good reputation
  • • Can reach millions per day
  • • Very cost-effective at scale

IP Lane Limits

New IP Addresses: Start with low limits (50-100 emails/day) and gradually increase based on reputation signals. Laneful's AI handles this automatically.

Warmed IP Addresses: Can handle millions of emails per month with up to 20 concurrent connections to ISPs.

ISP-Specific Limits: Each ISP (Gmail, Outlook, Yahoo) has different acceptance rates and connection limits.

Laneful's Retry Policy

When emails can't be delivered immediately, Laneful automatically retries using an intelligent backoff strategy.

How Retries Work

1

Initial Attempt

Email is sent to the provider's SMTP server immediately.

2

Rejection/Error

Provider rejects due to rate limits, temporary errors, or quota exceeded.

3

Intelligent Retry

Laneful queues the email and retries with exponential backoff for up to 3 days.

Retry Schedule

First retry: 5 minutes
Second retry: 15 minutes
Third retry: 1 hour
Subsequent retries: Every 4 hours
Maximum duration: 72 hours (3 days)

What Triggers Retries

• Rate limit exceeded (429 errors)
• Temporary server errors (5xx codes)
• Connection timeouts
• Quota exceeded responses
• Temporary DNS failures

Permanent Failures (No Retry)

Some errors are permanent and won't be retried:

• Invalid email addresses
• Domain doesn't exist
• Mailbox full (in most cases)
• Authentication failures
• Policy violations
• Blacklisted sender

Planning Your Email Volume

Use these guidelines to plan your email sending and avoid delays:

Gmail Volume Planning

Personal Gmail (500/day)

  • • Max 15,000 emails/month
  • • Best for: Small newsletters, transactional emails
  • • Consider spreading sends throughout the day

Google Workspace (2,000/day)

  • • Max 60,000 emails/month
  • • Better for: Medium businesses, regular campaigns
  • • Can handle burst sending better

Scaling Recommendations

Under 10K emails/month: Personal Gmail is sufficient. Perfect for startups and small applications.

10K+ emails/month: Consider IP Lanes when Gmail's daily limits become restrictive or you need reputation isolation.

High volume or mission-critical: IP Lanes provide unlimited capacity and full control over your sender reputation.

Campaign Timing Strategies

Spread Throughout Day

  • • Avoid hitting daily limits quickly
  • • Better for provider reputation
  • • Allows for urgent emails later

Schedule Large Campaigns

  • • Split large lists across multiple days
  • • Use Laneful's scheduling features
  • • Monitor delivery rates and adjust

Monitoring & Alerts

Laneful provides tools to monitor your sending limits and delivery status:

Dashboard Metrics

• Real-time sending rates
• Queue depth and wait times
• Provider-specific limits and usage
• Retry attempts and success rates
• Failed delivery reasons

Automatic Alerts

• Rate limit warnings
• High queue depth alerts
• Provider authentication failures
• Unusual bounce rate spikes
• Delivery delays beyond thresholds

AI Agent Insights

Laneful's AI agent continuously monitors your sending patterns and provides proactive recommendations:

• Suggests optimal sending times
• Recommends lane upgrades when limits are consistently hit
• Identifies patterns that might affect deliverability
• Provides early warnings about potential issues

Best Practices

Follow these practices to optimize your email delivery within provider limits:

✓ Do

  • • Monitor your sending patterns and adjust campaigns
  • • Use scheduling to spread large campaigns over time
  • • Set up alerts for rate limit warnings
  • • Test with small volumes before scaling up
  • • Keep track of daily/monthly usage across all channels
  • • Plan for growth with appropriate lane types

✗ Don't

  • • Send all emails at once without considering limits
  • • Ignore rate limit warnings or queue buildups
  • • Assume provider limits won't affect your use case
  • • Mix high-priority transactional with bulk marketing
  • • Forget about limits when planning campaigns
  • • Use personal Gmail accounts for business-critical emails

Ready to Optimize Your Sending?

Understanding limits is just the first step. Learn how to configure your lanes and implement best practices for reliable email delivery.