What are the recommended connection and message rate limits for wanadoo.fr and orange.fr to avoid throttling?
Michael Ko
Co-founder & CEO, Suped
Published 10 Jun 2025
Updated 15 Aug 2025
7 min read
Navigating the complexities of email deliverability to French internet service providers (ISPs) like Orange.fr and Wanadoo.fr requires a precise understanding of their connection and message rate limits. Failing to adhere to these guidelines can lead to email throttling, where your messages are intentionally delayed, or even outright rejections and blacklisting (or blocklisting).
I've seen many senders struggle with this, encountering issues such as slow delivery or errors like OFR_999, which indicate that Orange (and by extension Wanadoo, as they are part of the same group) is temporarily blocking your sending due to exceeding their limits. My goal here is to provide clear, actionable advice on how to configure your sending infrastructure to respect these specific thresholds and ensure your emails reach their intended recipients without unnecessary delays or disruptions.
How Orange.fr and Wanadoo.fr impose limits
Email service providers, including major French ones like Orange and Wanadoo, implement connection and message rate limits primarily to protect their infrastructure from overload and to combat spam. These limits dictate how many simultaneous connections your sending IP can establish with their mail servers and how many messages can be sent over each connection within a given timeframe. Exceeding these limits signals suspicious sending behavior, leading to throttling or a temporary blocklist (or blacklist) designation for your IP.
When your sending activity is throttled, it means Orange is intentionally slowing down your email delivery. This can manifest as significant delays in message transmission, which impacts the timely reception of critical communications. In more severe cases, persistent violation of these limits can lead to your IP address or domain being added to internal blocklists, resulting in outright rejection of your emails.
While Orange provides official guidelines, it's worth noting that real-world sending practices often involve more conservative limits to ensure optimal deliverability. These conservative settings help prevent throttling, even during peak sending times, by proactively staying well within the ISP's comfort zone. Understanding common connection and message limits imposed by different providers can give you a holistic view.
It is not just about the numbers themselves, but also about your sending reputation. A good reputation allows for more flexibility, while a poor one will cause even slight deviations to result in throttling or a blocklist entry. This is especially true for transactional emails, which need to arrive reliably and quickly.
Recommended SMTP connection limits
Orange's postmaster page explicitly states recommendations for SMTP delivery. For concurrent connections, the general advice is to limit to two simultaneous connections per sending IP address. Some email professionals, however, have observed better results by using even fewer, sometimes as low as one connection, especially for Wanadoo.fr.
If you are encountering "too many connections" errors, such as OFR004_104, even when your settings appear to be within limits, it's crucial to verify that your system is indeed enforcing those limits correctly. Sometimes, internal system configurations or transient network conditions can lead to momentary spikes that trigger these errors.
Conservative approach
Connections: Maintain 1 concurrent connection per outbound IP for both Orange.fr and Wanadoo.fr. This is a very safe setting to begin with.
Connections: Up to 2 concurrent connections per IP for Orange.fr, and 1 for Wanadoo.fr. This aligns with official Orange recommendations.
Considerations: Requires careful monitoring. More aggressive settings should only be attempted with excellent sender reputation and consistent performance.
Remember, the key is consistency. If your system isn't reliably enforcing your set limits, you might still run into issues even if the theoretical limits are followed. Always monitor your logs for email throttling and delays to ensure optimal performance.
Recommended message rate limits
Beyond concurrent connections, the rate at which you send messages within those connections is also critical. Orange suggests sending up to 100 messages per connection. However, the total volume of messages over a specific duration is also important to consider.
Some senders have found success by implementing a rate limit of approximately 90,000 messages per hour (or 3600 seconds) for their combined Orange and Wanadoo traffic. This translates to roughly 1,500 messages per minute. While a high number of messages per connection (e.g., 500) might seem efficient, it's often better to distribute the load with more connections and fewer messages per connection, or to pair a lower messages-per-connection count with an overall hourly sending limit.
It's vital to differentiate between connection limits and message rate limits, as both can lead to throttling if not managed correctly. A common mistake is to optimize for one while neglecting the other. For instance, having too few connections but trying to push too many messages per second can overwhelm the server, even if the total connection count is low. Conversely, too many connections with very few messages per connection can also be inefficient or trigger different flags.
Pacing your email sending to Orange.fr and Wanadoo.fr
Start low: When initiating sending to these domains, begin with very conservative rates, perhaps even lower than the recommended ones.
Gradual increase: Slowly ramp up your volume and rates while closely monitoring deliverability and bounce logs. This allows you to find the optimal balance for your specific sending patterns and IP reputation.
Monitor specific errors: Keep an eye out for specific errors like OFR_999 or OFR004_104, which directly indicate rate limiting or connection issues from Orange/Wanadoo.
Strategies to maintain good deliverability
Effective deliverability to Orange.fr and Wanadoo.fr goes beyond just setting correct connection and message rate limits. Your sender reputation plays a massive role. A clean sending history, low complaint rates, and proper authentication greatly influence how forgiving (or strict) these ISPs will be with your sending practices. Continuously monitoring blocklists is also important to quickly identify any listing that could impact your deliverability.
Implementing robust email authentication protocols such as SPF, DKIM, and DMARC is not optional. These protocols verify that your emails are legitimately from your domain and help prevent spoofing and phishing, which ISPs appreciate. A proper DMARC policy, in particular, signals to receivers like Orange that you are serious about email security and authentication, positively impacting your deliverability and reducing the likelihood of throttling.
Finally, maintaining clean mailing lists and promptly removing inactive or bouncing addresses is crucial. High bounce rates, especially to spam traps, can quickly damage your sender reputation and lead to stricter rate limiting or IP blocklisting. Regular list hygiene is a non-negotiable best practice for long-term email deliverability success. If email delivery to Orange is slow, check your list quality.
Limit type
Orange.fr recommendation
Observed practical limit for Orange.fr/Wanadoo.fr
Concurrent connections
Up to 2 per sending IP address
1-2 per outbound IP (some prefer 1 for Wanadoo.fr)
Messages per connection
Up to 100 messages
100 messages per connection is a good guideline, though some have used up to 500 messages per connection, carefully.
Hourly message rate
Not explicitly stated as a hard limit
Up to 90,000 messages per 3600 seconds (per hour) across all connections to Orange/Wanadoo.
Key takeaways for Orange and Wanadoo deliverability
Managing connection and message rates for Orange.fr and Wanadoo.fr is a dynamic process. It requires not only initial configuration but also continuous monitoring and adaptation. By adhering to the recommended limits, implementing proper authentication, and maintaining a healthy sender reputation, you can significantly reduce the risk of throttling and ensure consistent deliverability to these important French ISPs.
Remember, email deliverability is a marathon, not a sprint. Consistent effort in following best practices for handling email sending rate and connection limits will yield the best results over time, keeping your emails out of the spam folder and in the inbox. This proactive approach ensures your email program remains effective and reliable.
Views from the trenches
Best practices
Start with conservative connection and message rates, then gradually increase as your reputation allows.
Implement a system that accurately throttles connections and message rates per IP and per domain.
Regularly monitor bounce logs for specific Orange/Wanadoo error codes like OFR004_104 and OFR_999 to adjust limits.
Common pitfalls
Assuming official recommendations are the maximum, when practical limits might be lower for new or low-reputation senders.
Neglecting to account for all sub-domains or sending IPs when setting global rate limits.
Failing to adapt rates based on real-time feedback from bounce messages and deliverability reports.
Expert tips
Consider adjusting connection limits by MX record as well, not just by domain or IP, for more granular control.
Beyond connection and message rates, ensure your domain has strong SPF, DKIM, and DMARC authentication in place.
Regularly check for your IPs or domains on common blocklists to proactively address reputation issues.
Expert view
Expert from Email Geeks says they sometimes see OFR004_104 'too many connections' errors even when their settings limit to three connections, indicating that internal system checks are crucial.
2020-12-15 - Email Geeks
Expert view
Expert from Email Geeks says their settings are currently two connections to Orange.fr and one to Wanadoo.fr per outbound IP, planning to refine by MX someday.
