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Guide on How to Format International Phone Numbers

|  6 min
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In this article

Why It’s Important to Properly Format International Telephone Numbers

In the current economy, business organizations must routinely deal with suppliers, stakeholders, and customers from all corners of the globe. Together with email, phone numbers provide the most direct way of communicating with these contacts – whether it’s through SMS text messaging and notifications, or via a dedicated messaging platform like WhatsApp.

Phone numbers are part of the essential bank of data that businesses use to coordinate with supply chain partners, contact customers and prospects, personalize interactions, and put their sales, marketing, customer service and other teams in a position to succeed.

Using the wrong phone number format can slow down these teams when they try to call prospects and customers. Inconsistent phone number formatting can break integrations between mission-critical business systems, cause data issues between different platforms, and create confusing duplicate records. In addition, poor or inconsistent formatting can make it difficult to use phone number data in manual applications.

This applies equally to local contacts and international ones. The diversity of phone number conventions that apply in various countries in particular makes it difficult to maintain consistency and accuracy across applications that rely on formatting accuracy. This includes platforms such as WhatsApp, which requires users to always send their phone number in full international format, and SMS text, which is heavily dependent on proper formatting to guarantee that messages can be delivered to their desired destinations. 

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So, how can you make sure that you get your international phone number formatting just right? Take the following steps:

Add the Right Country Code

A telephone number in full international format includes a plus sign (+), then the relevant country code, city code, and local phone number.

Especially when using phone numbers in the context of digital electronic systems and communications (such as SMS marketing or on a messaging platform like WhatsApp), adding the correct international country code is a critical matter. Without the correct formatting, a computer or digital platform might interpret the phone number as something else altogether.

A standard international dialing or communications directory should provide you with the relevant country code designation. For instance, the country code for the United Kingdom (UK) is “+44,” while the country code for the United States (USA) is “1.” So if a contact in the United States has the area code “408” and phone number “XXX-XXXX”, you’d enter +1 408 XXX XXXX as their international phone number for WhatsApp dialing

However, there are some points to bear in mind.

Countries may sometimes format phone numbers in different ways. Depending on the location that you are dialing from or the device attached to a particular number, the same phone number may use different conventions.

For example, countries may use an international direct dialing prefix, also known as a dial out code. Each prefix is designed to select a particular phone circuit for placing an international call. In addition, individual countries may also use a national direct dialing prefix for in-country calls.

To complicate matters further, some countries use periods to separate the numbers and improve readability. Some use dashes, others use parentheses, and some use spaces.

The International Telecommunication Union (ITU) recommends the sequence 00 as a standard for all international call prefixes. However, not all nations adhere to this. For example, Canada and the United States use 011, Japan uses 010, and Australia uses 0011..

Use E.164 Formatting

At present,  the E.164 phone number format is the international phone number formatting standard that applies across the globe. E.164 was originally designed to provide a standardized and consistent format that enabled machines to use phone numbers in a reliable fashion. It has since become an enabling communications standard for various classes of services and software.

The design of an international E.164 number includes all of the information needed to successfully route a call or SMS message to an individual subscriber on a national public telephone network. E.164 is an internationally recognized format that will work with nearly any software, and is intended particularly for applications where it’s important that those solutions have the ability to recognize an international country code, area codes, and the actual phone numbers themselves, within a given data string.

An international phone number in E. 164 format uses this template:

[+][country code][area code][local phone number]

Note the following points:

  • A telephone number in E. 164 format can have a maximum of 15 digits.
  • The first part of the telephone number (the country code) has from one to three digits.
  • The second part of the number is the national destination code (NDC).
  • The last part is the subscriber number (SN).
  • The NDC and SN together are collectively known as the national (significant) number.
  • The E. 164 formatting standard uses no spaces, no dashes, no parentheses, and no periods.

Validate by Using the Phone Number Parser 

The Phone Number Parser demo is part of a piece of software that Google uses to check phone number formatting in Android phones. It has since been repurposed and made available online as an instrument for users to check whether a phone number is correct, or how it should look in E.164 formatting.

Why You Need Proper International Phone Number Formatting for Your Business Systems Integration

Both your internal and outward facing business operations in the global economy require accurate and timely communication with your list of contacts. This communication will take place in a number of different contexts, and  across a number of different platforms. For example, contact data is integral to the work of sales and marketing software, supply chain and vendor management systems, Customer Relationship Management (CRM), and Enterprise Resource Planning (ERP). 

As we have observed, inconsistent phone number formatting can break the integration between various business systems, and create data issues between platforms. Ideally, you want to make sure that you choose the right format for international telephone numbers, so that you can effectively meet the needs of the different platforms and teams that will use this contact information most frequently.

Technology solutions like auto-dialers and virtual call centers can typically handle some of this issue for you. However, there may be cases where you are calling from several locations or manually calling customers, so it’s important to get this information right.

Using E.164 formatting for international phone numbers ensures that you have a consistent format that will be guaranteed to work with most software integrations. E.164 formatting is also the best choice if you primarily use phone numbers for click-to-dial software integrations and automation.

Expanding Your International Reach

With the correct international phone number formatting in place, you can then concentrate on optimizing the scope and content of your business communications.

Here at IDT Express, our cutting-edge SMS platform provides a bulk messaging facility capable of transmitting 25,000 messages per second to recipients in over 70 countries, using our local DID numbers. You can also receive messages in 14 different countries on your SMS-enabled phone numbers.

With IDT’s  two-way messaging, you can engage in interactive conversations with your audience and allow recipients to respond to your SMS messages, enabling a seamless communication loop. Intelligent routing algorithms  ensure that your SMS messages reach their intended recipients seamlessly.

Using IDT’s  Multimedia Messaging Service (MMS) capabilities, you can go beyond plain text and enrich your SMS messages with multimedia content. Our platform supports multimedia messaging via WhatsApp, Viber, and Facebook Messenger.

To take your business systems integration to the next level, you can use the IDT Express SMS API (Application Programming Interface), to swiftly integrate IDT’s carrier-grade platform into your current systems or applications. With our SMS API, you can seamlessly build customer journeys by fostering interactive conversations, all within the framework of your app.

Providing a user-friendly wizard-driven code generation process that is fast and effortless to utilize, the IDT Express SMS API lets you easily schedule SMS, MMS, or WhatsApp messages to be sent at a specific date and time in the future with a simple API call.

With IDT, you have the capability to send bulk text messages internationally to multiple countries at the same time – provided you input the correct country codes when uploading international phone numbers to ensure proper routing.

To find out more about how IDT’s Bulk SMS platform and IDT Express SMS API can help improve your international business communications, book a demo.

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