AVOXI - Five9 SIP Forwarding Configuration

To expand your number inventory you can purchase numbers from AVOXI and forward them into your Five9 account.  Use our below step-by-step guide to set up Genius SIP Forwarding and Five9 guides to get started.

Setup Your Five9 Account

VoIP (Voice over Internet Protocol) Services and phones should be on a network segment separate from the Five9 workstation firewall requirements. Communication to Five9 is done through standard DNS requests. Agent desktops should resolve all server names for the Five9.com domain.

The URL standard contains a port specification. For example, www.domain.com means http://www.domain.com:80. The default port is generally omitted. Five9 URLs do not use a port other than 80.

Five9 uses certain TCP/UDP ports for Five9 applications and communications. Customers must avoid using the following TCP/UDP ports for any third-party services or applications running on agent desktop computers: 8080, 9998, 11000, 30059.

Five9 recommends that you configure your firewall to allow traffic only at the TCP/ UDP ports and source destination to or from any of the Five9 data center IP address ranges/ internet domains listed in this section.

  • Whitelisted Internet Domains and IP Addresses

  • SIP Firewall Note

  • TCP/UDP Port Requirements for Softphone Customers

  • TCP/UDP Port Requirements for Gateway Customers

  • TCP/UDP Port Requirements for PSTN Customers

  • TCP Port Requirements for FTP/SFTP

  • Network Requirements for Five9 Video Engagement

  • API Customers

  • Third-Party Software

  • Five9 Quality of Service (QoS) Features

  • Workstation QoS Option

  • Network QoS Option 

Whitelisted Internet Domains and IP Addresses

Ensure that you add Five9 Internet domains and IP addresses to your whitelist of safe Internet and IP addresses. You may add IP addresses to your whitelist at several points in your network. Be sure that IP address restrictions defined in your firewall match the Five9 IP address ranges and domains listed here. The whitelist overrides SPAM filters and blacklists.

  • Five9 IP Address Ranges

  • Five9 IP Addresses for Global Voice

  • Five9 Internet Domains

  • CounterPath Softphone Requirements

  • Performance Dashboard 

Five9 IP Address Ranges‌‌

To avoid potential service impacts, you must add Five9 IP addresses to a whitelist in your IPS solutions.

Note If your network security protocols restrict the external IP addresses that you can use, contact your Five9 representative for assistance in configuring the Five9 email.

If you use Microsoft Exchange 2010, email delivery to your users may be delayed unless you set the value of MaxAcknowledgementDelay to 1 second.

US IP Ranges

Location of Data Center

CIDR Format –

Santa Clara – – –


US IP Ranges

Location of Data Center

CIDR Format –

Atlanta – -

In the US, EU data centers are optional.






EU IP Ranges

Location of Data Center

CIDR Format –

London – /24 –

Amsterdam – – /28 – /28 –

In the EU, US data centers are optional.



Note IPS solutions are designed to block real-time traffic that matches certain attack behavior. Because every IPS solution responds to traffic differently, and you may receive daily updates to attack signatures, the behavior of IPS solutions can be unpredictable. False positives are possible.

If your intrusion prevention systems (IPS) overreact to normal VOIP (SIP and RTP) traffic to and from Five9, you may experience service interruptions.


Five9 IP Addresses for Global Voice

These production IP addresses apply only to Five9 Global Voice.


Sao Paolo



To view further details please refer to the Five9 technical guide or reach out to a Five9 support team.

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November 29th, 2023


Criss Soto

Updated By:

Jeff Cook



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configuration, sip forwarding

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