Three Effective Phone Verification Methods

To check if a phone number is real, you can use a callback test, look up the number’s carrier and line type, check its format against E.164 standards, or watch for VoIP patterns that signal non-geographic numbers. For businesses verifying numbers at scale, a phone validation API automates all of this in real time.

Verifying the authenticity of phone numbers has become essential for ensuring secure transactions, preventing fraud, and maintaining accurate user databases. Whether you’re a business owner or app developer concerned about privacy, having reliable methods to verify phone numbers is crucial. In this blog post, we’ll cover three ways of verifying if a phone number is real and discuss their benefits.

#1: Manual Checks

There are a few quick practical ways to manually check whether a phone number is real or fake:

• Callback test: Dial the number. A real, active number will ring or go to voicemail. A disconnected or fake number typically returns an error tone or automated “not in service” message.
• Format check: Real phone numbers follow the E.164 standard, or a country code followed by a subscriber number, with no spaces or special characters. A number with too many or too few digits is likely invalid.
• Carrier lookup tools: Online carrier lookup tools can tell you whether a number is registered to a carrier and what line type it is (mobile, landline, or VoIP). Unregistered numbers or numbers that return no carrier data are red flags.
• VoIP patterns: Numbers from VoIP providers (like Google Voice or Skype) are technically valid but are frequently used in fraud and spam. If a number’s line type returns as VoIP, treat it with extra scrutiny depending on your use case.

These manual checks work for one-off lookups but don’t scale. If you’re verifying thousands of numbers (for a lead list, a user database, or real-time form submissions), you need an automated solution.

#2: Real-Time APIs

Phone Validation API

One of the most reliable methods to verify a phone number is by using Phone Validation API. This phone validation leverages extensive databases and algorithms to indicate whether a given phone number is valid and active or disconnected and inactive. It also provides additional information such as the carrier, line type, and Phone Activity Score.

Benefits:

• Accuracy: Phone Validation API offers high accuracy in determining whether a number is valid or not based on authoritative telco signals.
• Efficiency: Phone verification is done in real-time, allowing for instant feedback to users or automated processes.
• Data Enrichment: Phone Validation API can provide supplementary details about the phone number, such as line type, carrier, and pre-paid status, aiding in building a more comprehensive user profile.

Phone-to-Name Match with Real Contact API

This method involves verifying a phone number by cross-referencing it with Real Contact API. This phone verification API is particularly useful when you need to establish a genuine connection between a phone number and a person’s identity. At Trestle, we have the best-in-class phone data coverage. Our name coverage is 90%, which means we will have a name for the phone number queried 90% of the time – better than anyone else. Along with having the best phone-to-name match, Real Contact API also includes contact grading to help prioritize leads most likely to answer, and IP-based intelligence signals that help gauge the legitimacy of the contact.

Benefits:

• Phone-to-Name Match: Have confidence that you’re contacting the right person.
• High Assurance with Phone Contact Grade: Being able to verify a lead’s identity adds a layer of trust and certainty for businesses.
• IP-Based Intelligence: Assessing IP signals helps gauge the authenticity of the interaction.
• Compliance: Businesses can confirm the phone still belongs to the person they intend to reach and that it has not changed hands or been reassigned. This ensures compliance with outbound dialers and text messaging right party contact requirements.
• Security: Verifying a phone number can prevent fraudulent activities and impersonation attempts.

#3: SMS Verification

SMS verification is a widely-used method for confirming the authenticity of a phone number. By integrating SMS verification into your application or platform, you can add an extra layer of security that requires users to verify their phone numbers before gaining access. SMS phone verification allows you to send verification codes to users’ phone numbers. Users then input the received code into your application to complete the verification process.

Benefits:

• Two-Factor Authentication (2FA): SMS verification adds an extra layer of security, making it difficult for unauthorized users to gain access.
• Ease of Use: Implementing a SMS verification is straightforward, even for developers without extensive experience in telecommunications.