# Is Google Voice a VoIP number? How it is classed

> Is Google Voice a VoIP number? Yes: line-type databases class it as non-fixed VoIP, and OpenAI says it does not support Google Voice numbers.

- URL: https://realsimnumbers.com/guides/is-google-voice-a-voip-number
- Last updated: 2026-10-19
- Publisher: RealSIM Numbers (https://realsimnumbers.com/)

Why a Google Voice number fails where a SIM-based mobile number passes.

**Quick answer — Is Google Voice a VoIP number?**

Yes. Google Voice numbers are internet numbers that need no SIM, and Twilio's line-type database names Google Voice as its example of "nonFixedVoip". OpenAI says it does not support Google Voice for verification and Microsoft refuses VoIP numbers, as checked in October 2026. A SIM-based mobile number is classed "mobile" instead.

## How do databases class Google Voice?

Twilio defines "nonFixedVoip" as "a virtual phone number obtained online without requiring a physical device. For example, Google Voice or Enflick." Enflick is the company behind TextNow. Most US sign-up forms that check line type rely on this kind of classification.

## Which services refuse it?

| Service | What its help centre says |
| --- | --- |
| OpenAI (ChatGPT) | Does not support landline, VoIP, Google Voice or premium numbers for verification |
| Microsoft | "VOIP numbers cannot be added as a way to sign in or get verification codes." |
| Telegram | "Telegram accounts can only be connected to a mobile number." |
| Discord | VoIP, burner and landline numbers cannot be used for phone verification |

*Checked 2026-10-18; see the service pages for sources.*

## Which line types exist, with examples?

| Line type | Twilio definition | Examples named by Twilio |
| --- | --- | --- |
| mobile | "A mobile number that generally can receive SMS messages." | Numbers on mobile carriers' SIM cards |
| fixedVoip | "A virtual phone number associated with a physical device." | "For example, Comcast or Vonage." |
| nonFixedVoip | "A virtual phone number obtained online without requiring a physical device." | "For example, Google Voice or Enflick." |

*Twilio Lookup documentation, read on 2026-10-18.*

A service that wants mobile numbers usually blocks nonFixedVoip first, because such numbers can be created online in seconds. Some also block fixedVoip and landlines.

## Why do services distrust phone codes on VoIP numbers?

Because SMS codes are a common target. Microsoft writes that "SMS-based authentication is now a leading source of fraud" and is phasing SMS out for personal accounts. NIST classes phone-based verification as "restricted" and asks verifiers to weigh signals such as "SIM change, number porting". A number that needs no SIM at all is the easiest to obtain, so it is the first one refused.

## What can I use instead, and what does it cost?

| Option | Line type | Price | Keeps the number |
| --- | --- | --- | --- |
| Your own mobile | mobile | Your plan | Yes |
| Single-use number at RealSIM Numbers | mobile (SIM) | $0.36 (Google) to $1.12 (WhatsApp), US | No |
| 30-day US rental at RealSIM Numbers | mobile (SIM) | $3.60 (one service) | 30 days |
| 30-day US line at TextVerified | mobile (SIM, per its FAQ) | $4.80 (WhatsApp line) | 30 days |

*Prices as of 2026-10-18; TextVerified figure from its own page. The median public price of a US WhatsApp code was $1.50 across six providers that day.*

A number on a SIM card: your own mobile, a second prepaid SIM, or a SIM-based number from a provider. For a one-off code, a single-use non-VoIP number is enough; for repeated logins, a rental keeps the same number.

**Get a SIM-based US number** From $0.36 per code. [Get a number](https://realsimnumbers.com/en/offres?country=US) · [See pricing](https://realsimnumbers.com/pricing)

## Frequently asked questions

### Is TextNow a VoIP number?

Yes. TextNow numbers come from Enflick, which Twilio cites with Google Voice as an example of non-fixed VoIP.

## Related pages

- [US non-VoIP numbers](https://realsimnumbers.com/non-voip-numbers/united-states)
- [What is a non-VoIP number?](https://realsimnumbers.com/guides/what-is-a-non-voip-number)

## Sources

1. [Twilio Lookup: Line Type Intelligence](https://www.twilio.com/docs/lookup/v2-api/line-type-intelligence) (checked 2026-10-18)
2. [Microsoft Support: SMS codes for personal accounts](https://support.microsoft.com/en-us/accounts-billing/manage/microsoft-to-stop-sending-sms-codes-for-personal-accounts) (checked 2026-10-18)
3. [NIST SP 800-63B rev. 4](https://pages.nist.gov/800-63-4/sp800-63b.html) (checked 2026-10-18)
4. [TextVerified: WhatsApp service page](https://app.textverified.com/services/whatsapp) (checked 2026-10-18)
5. [OpenAI Help: VoIP and Google Voice numbers](https://help.openai.com/en/articles/8983024-can-i-use-a-premium-number-landline-google-voice-or-other-voip-phone-number) (checked 2026-10-18)
6. [Microsoft Support: VoIP numbers](https://support.microsoft.com/help/409090c4-92b5-42b9-8ae6-bcc97e62fc48) (checked 2026-10-18)
7. [Telegram FAQ](https://telegram.org/faq) (checked 2026-10-18)

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RealSIM Numbers: RealSIM Numbers is a non-VoIP (real SIM) provider of virtual phone numbers for receiving SMS, paid in crypto with no ID upload.