Grandstream
Grandstream HT813 Hybrid ATA 1 FXS 1 FXO Port Analog Telephone Adapter HT813
PO and Net 30 accepted for schools, government and healthcare.
Description
Description
Grandstream HT813 Hybrid ATA β Connect Analog Phones to VoIP with PSTN Lifeline Backup
The Grandstream HT813 is a versatile hybrid analog telephone adapter (ATA) with both FXS and FXO ports, allowing you to bridge analog phone systems to your VoIP network while retaining PSTN lifeline backup. Ideal for businesses, home offices, and service providers upgrading to IP communications without abandoning existing analog infrastructure. Backed by Reef Telecom's industry-leading 10-year warranty and free shipping on orders over $300.
Key Features
- 1 FXS port and 1 FXO port supporting 2 SIP profiles
- PSTN lifeline support β FXS port hard-relays to FXO port during power outages
- Dual 100Mbps Ethernet ports (LAN and WAN) with integrated NAT router
- T.38 Fax-over-IP for reliable fax transmission
- 3-way voice conferencing per port
- Strong AES encryption with per-unit security certificate
- Failover SIP server for automatic switchover if primary server disconnects
- TR-069 automated and secure remote provisioning
- HD voice quality with support for G.711, G.729A/B, G.723.1, G.726, iLBC, and OPUS codecs
- Ultra-compact form factor
Compatibility & Use Cases
The HT813 is perfect for small businesses, home offices, and service providers looking to convert analog phones, fax machines, or alarm systems to VoIP. Its FXO port enables PSTN pass-through and emergency call routing, making it a reliable choice for environments where uptime is critical. Compatible with major SIP platforms and IP PBX systems including Grandstream UCM, Asterisk, FreePBX, and hosted VoIP services.
Specs & Details
Specs & Details
- Condition
- New
- Warranty
- 10-Year Reef Telecom Warranty
- Manufacturer Part Number
- GRANDSTREAM-HT813
- Reef SKU
- GRANDSTREAM-HT813-R
- UPC
- 6947273702634
- Brand
- Grandstream
Shipping & Warranty
Shipping & Warranty
Free ground shipping on orders over $300 (contiguous US). Same-day dispatch on orders placed before 4 PM EST.
All products include our industry-leading 10 Year Warranty backed by Reef Telecom.

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