FCC Rule Requiring Support for Dialing 988 to Reach the National Suicide Prevention Hotline


On July 16, 2020 the Federal Communications Commission (FCC) passed rules that established 988 as a nationwide 3-digit dialing code for Americans in crisis to connect with suicide prevention and mental health crisis counselors on the National Suicide Prevention Hotline. The rule applies to all phone service providers and goes into effect on July 16, 2022. The current number for the hotline is 1-800-273-8255 (1-800-273-TALK). Veterans and Service Members can reach the Veterans Crisis Line by pressing “1” after dialing, chatting online at www.veteranscrisisline.net or texting 838255.

The rule also requires that all providers who currently support seven (7) digit dialing and use 988 as an exchange must implement ten (10) digit dialing to ensure 988 calls get routed correctly. The exchange are the first three (3) digits in a seven (7) digit phone number or are the three (3) digits after the area code for a US based number. 
The rule implies that multi line telephone systems (MLTS) like Microsoft Lync, Microsoft Skype for Business, Microsoft Teams, and other vendor solutions should support 988 dialing and routing to a telephony provider. The rule has implications for deployments that are still sending seven (7) digit phone numbers to their carrier. 

Implementing 988 Dialing in Lync, Skype for Business and Microsoft Teams 

  1. To make things simple in the following discussion, we’ll refer to your Lync, Skype for Business or Microsoft Teams deployment as the phone system. 
  2. We will also assume that your phone system follows the Microsoft best practice to normalize phone numbers into the ITU e.164 format. 
  3. We will not cover how to modify Dial Plans, Voice Routes, PSTN Usages, etc. These are all well documented by Microsoft and other sources. Enabling Technologies is ready to help you make these changes. 

Gather Phone Provider Information 

  1. The first step in implementing 988 dialing is to check with your phone provider. This is the telephone company your system is attached to. It is the provider of your: 
  2. Analog Circuits 
  3. Primary Rate Interface (PRI) service 
  4. SIP Trunks, etc. 
  5. Ask them when they will support receiving calls to 988 from your phone system. They should support this no later than July 16, 2022. 
  6. You will also need to ask them in what format the destination number for these calls should be presented. It will probably be “988” or “+988”. 

Dial Plan Configuration 

  • Create a new normalization rule for 988 dialing. 
  • The rule should match when a user dials “988”. 
  • The translation normalizes the dialed number to “+988”. 
  • Rules that are most specific should be at the top of the dial plan. Insert this rule adjacent to similar rules. 
  • Test the rule by itself and then as part of the whole dial plan. 
  • Here is a sample dial plan with the new rule: 
  • For Teams deployments: 
  • If the Global (org-wide default) dial plan does not have any normalization rules, “988” will not be translated int “+988”. 
  • This rule should be added to and tested on all dial plans assigned to your users. 

Voice Policies, PSTN Usages and Voice Routes 

  • Create or modify a voice route to handle calls made to the hotline: 
  • Assign the route to a PSTN Usage and assign the usage to your Voice Policies. 

Session Border Controller or PSTN Gateway Configuration 

  • Add a route, as needed, to route the call to the telephony provider. 
  • If the provider does not want the number in the “+988” format, add a rule to manipulate the number into the required format. 
  • The number manipulation could have been done in the phone system. Create the manipulation wherever you have previously created manipulations. 


  • Make a test call from Microsoft Lync, Microsoft Skype for Business or Microsoft Teams to the to the Suicide Prevention Hotline: 
  • Verify that the call completed and that you have two (2) way audio. When making the call, advise the agent answering the call that you are making a test call! 
  • Make sure that the call used the expected dial plan, route, PSTN usage and voice policy assigned to the test user. 
  • Verify that the call used the correct route and manipulation (if needed) on the SBC. 

The End of seven (7) Digit Dialing? 

The FCC rules instruct telephony providers who currently support seven (7) digit dialing and use 988 as an exchange to implement ten (10) digit dialing. The FCC added this requirement to ensure the correct routing of calls to the Suicide Prevention Hotline. 

Seven (7) digit dialing has been around for decades. Over time, there are fewer and fewer telephony carriers supporting it. The seven (7) digits are comprised of the three (3) digit exchange and four (4) digits of the individual number. The exchange cannot be 911 nor can it be 211, 311, 411, 511,611,711 or 811. The exchange, 988 is permitted. To prevent accidental dialing of 988, the FCC has added the rule requiring the carriers to stop support for dialing seven (7) digit numbers. 

Microsoft Lync, Microsoft Skype for Business or Microsoft Teams implementations can permit seven (7) digit dialing in the Dial Plan based on the needs of the client. We still come across clients who do this. We even have some clients who still send seven (7) digits to their carriers for local calls. This rule will affect these customers. The rule does not require you to drop support for dialing seven (7) digit numbers by your user. The rule requires that your carrier drop support for you sending seven (7) digit numbers to them. 

On a side note, if you are still supporting seven (7) digit dialing in your phone system, Enabling Technologies recommends that you start transitioning away from it. We recommend in most cases that you require eleven (11) digit dialing (dial 1 + 10 digits) for US domestic numbers. Supporting ten (10) digit dialing or ten (10) digit dialing with an optional leading “1” should be fine in most cases. 

What do you do if you are currently sending seven (7) digit US domestic destination numbers to your carrier? 

  • The carrier should send you plenty of notice of when they are going to drop support for seven (7) digit destination numbers. 
  • The rule requires that the carriers drop support for seven (7) digit numbers and that they require ten (10) digit numbers for all domestic US calls. 
  • A carrier could decide to support one (1) or more of these formats for domestic US calls: 
  • Ten (10) digits like 443-625-5192. 
  • Eleven (11) digits like 1-443-625-5192. 
  • E.164 like +1-443-625-5192. 
  • If the information from the carriers is unclear or ambiguous, CONTACT THE CARRIER FOR CLARIFICATION! Make sure you know: 
  • What format(s) they are going to support. 
  • When they will start supporting the new format(s). 
  • When they will stop supporting the seven (7) digit format. 
  • If they support more than one of these options, use the one with the most digits. Choose eleven (11) over ten (10) digits and E.164 over anything else. This is the best option for the long run. 
  • Add a manipulation rule to your SBCs and PSTN Gateways to manipulate US domestic destination numbers into the appropriate format for the carrier. Enable this rule on the date the carrier provided for supporting the new format. 
  • If logistically possible, test this before the carrier drops support for seven (7) digit dialing. 


  • The FCC is requiring that US-based telephony carriers support routing of the number “988” to the National Suicide Prevention Lifeline by July 16, 2022. 
  • The FCC rule does not require support for “988” dialing on company-owned and administered MLTS’s but seems to imply it. 
  • Clients with Microsoft Lync, Microsoft Skype for Business or Microsoft Teams voice implementations should add support for dialing “988” to their Call Flows. 
  • Check with your carrier to find out when they are going to support this rule and in what format(s) they require\support when sending “988” calls to them. 
  • Carriers are also required to drop support for seven (7) digit dialing to prevent problems when dialing “988”. Though this type of dialing has been heading towards extinction, there are still some carriers who support or require this for local calls. 
  • If your carrier currently supports seven (7) digit dialing and your Microsoft Unified Communications system is sending them seven (7) digits, find out when the carrier is going to drop support for seven (7) digits and what the new required format(s) will be. Remediate your environment to support the new format. 


Engage the eGroup | Enabling Technologies team with “been there, done that” experience,  we know all of the “minefields” to prevent missteps.

John Miller

John Miller

Cloud Solutions Architect - eGroup | Enabling Technologies

Last updated on July 31st, 2023 at 12:59 pm