RoadRunner / Time Warner Cable is one of the large cable companies in the US. They handle mail for a large number of domains, many of them in the format They also provide business grade hosting, but the mail filters for the hosting customers are different than the filters for email. This page focuses on the consumer mail system.

Delivering to RoadRunner

RoadRunner does limit the number of emails that can be sent based on a number of factors, including sender reputation. However, they do not publish specific limits. Road Runner requires that the sending server’s reverse DNS entry and forward DNS entry match; that is, the IP address connecting to our servers should resolve to a hostname that resolves back to the IP address. Connecting servers that do not meet this requirement may see more restrictive rate limiting than servers that have matching forward and reverse DNS. They also monitor senders for the number of deliveries to non-existent address and if the number of unknown addresses goes over a threshold then RoadRunner may block future mail from that source.

Important links and references

Postmaster pages

RoadRunnder does provide a postmaster site with information for senders.

Feedback loop

RoadRunner does provide a FBL and accepts signups at their FBL page.


There is no whitelist provided for senders, however, participants in the FBL program do see more flexible rate limits than senders not in the FBL program.

Certification Services

RoadRunner uses the Return Path Certified whitelist in mail delivery decisions. Mail from IPs on the Return Path Certified list will see better delivery at RoadRunner domains.

Support for Senders

RoadRunner provides an extensive list of return codes so that senders can troubleshoot delivery problems themselves. They also provide contact for questions unanswered by the support pages.

Known spamfilters

RoadRunner uses a number of commercial spamfilters and blocking lists, including Cloudmark CSI{.isp-blocklist], Spamhaus ZEN, and the Return Path Reputation Network Blacklist. They also maintain their own blocklist internally.


Updated 3/13/2014

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