Neutral Tandem Phone Number Lookup

What Is Neutral Tandem and Why Is It on My Caller ID?

Neutral Tandem, Inc. is the legal company name behind the carrier Inteliquent, which is owned by Sinch. The company rebranded to Inteliquent years ago, but "Neutral Tandem" remains the registered carrier of record on many phone number blocks, so lookup tools still display it, usually with a state suffix such as "Neutral Tandem-Illinois" or "Neutral Tandem-California".

Like Inteliquent and Onvoy, Neutral Tandem is a wholesale network: it supplies numbers and calling infrastructure to VoIP apps, business phone systems, and other carriers. The name on your caller ID identifies the network that issued the number, not the person or company calling you.

Is a call from a Neutral Tandem number spam?

Not automatically. Plenty of legitimate calls ride on this network: business lines, notification services, and calls from internet-based phone apps. But because these are VoIP numbers that can be provisioned in bulk without a SIM card, scammers use them more often than regular mobile numbers.

Never share a verification code with a caller and don't trust the caller ID name alone. Use the lookup tool above to confirm the carrier and line type. Block unwanted numbers, enable your carrier's spam filter, and report persistent offenders at donotcall.gov.

How to Identify Neutral Tandem Numbers Using Abstract API

Abstract's Phone Number Validation API offers a reliable way to check whether a U.S. phone number belongs to the Neutral Tandem network.

Step 1: Sign Up and Get Your API Key

Sign up for a free account with Abstract API. Your unique API key is on your account dashboard after you register.

Step 2: Send a Request to the API

Send a GET request with your API key and the phone number in international E.164 format:

https://phonevalidation.abstractapi.com/v1/?api_key=YOUR_API_KEY&phone=+15558675309

Step 3: Interpret the Response

The JSON response includes the number's validity, country, location, line type, and carrier. If the carrier field returns "Neutral Tandem" (often with a state name), the number runs on the Neutral Tandem / Inteliquent network.

Why Identifying a Neutral Tandem Phone Number Is Important

Knowing if a number belongs to the Neutral Tandem network helps improve communication efficiency and security.

• Improved Communication Routing - Systems can direct calls or messages more efficiently when the carrier is known.
• Enhanced Security Measures - Verifying a number's carrier and line type helps flag virtual numbers before processing transactions.
• Accurate Database Management - Up-to-date carrier information keeps contact data clean and reliable.
• Better Deliverability - Carrier data helps avoid sending SMS to numbers unlikely to receive them.

Why Use Abstract API for Neutral Tandem Phone Number Lookup?

Abstract API provides a reliable and fast method for phone number validation, with accurate carrier data for any number, including those on the Neutral Tandem network.

• Real-Time Data Access - Every lookup returns the most current carrier information available.
• Scalable Architecture - The system handles high volumes of requests without performance degradation.
• Simple Integration - Clear documentation lets developers add phone validation with minimal effort.
• Global Coverage - The API supports phone numbers from 190+ countries.

Looking for more phone intelligence tools? Try our phone number lookup tool, or explore the Phone Validation API for programmatic validation and carrier detection. You can also browse every carrier we cover in the phone number carrier checker directory.

Phone spam rarely travels alone. If you are also getting suspicious emails, run the sender's address through our free email risk checker, or use the Email Reputation API.

Frequently Asked Questions

Why does a phone number lookup show "Neutral Tandem" with a state name?

Carriers register number blocks per state, and lookup databases display the registered legal entity for each block. Neutral Tandem registered its numbers state by state, which is why you see labels like "Neutral Tandem-Illinois" or "Neutral Tandem-Michigan". They all belong to the same national network, now operating as Inteliquent under Sinch.

What is the relationship between Neutral Tandem, Inteliquent, and Sinch?

Neutral Tandem, Inc. is the legal name of the company that rebranded as Inteliquent, which merged with Onvoy in 2017 and was acquired by Sinch in 2021. A lookup may show any of those names depending on the number block, and they all point to the same carrier family.

Is Neutral Tandem itself a scam company?

No. It is a legitimate, licensed United States carrier. Scammers sometimes use VoIP numbers issued through its network because they are cheap to create in bulk, but the carrier transports the call; it is not the caller.

Can I find out exactly who called me from a Neutral Tandem number?

Not from a carrier lookup alone. A lookup returns the carrier, line type, and registered location, enough to judge whether a call looks trustworthy, but not the caller's name. If a caller claims to be your bank or a government agency, hang up and call back on the official number.

What line type do Neutral Tandem numbers appear as?

Usually fixed or non-fixed VoIP under the line_type field, since the network primarily serves internet-based calling services. A VoIP line type is itself a useful risk signal when evaluating an unknown number.

What number format is required when querying carrier data?

Submit numbers in international E.164 format with a leading + sign (for example, +15558675309 for a US number). This ensures consistent parsing across the 190+ countries the API supports.