A UIFN (Universal International Freephone Number) is a toll-free number that works the same way across many countries. Instead of setting up a separate toll-free number for every market you serve, a UIFN lets you use one global number that customers can dial for free from anywhere it's active.

This article explains what a UIFN is, its key characteristics, and a few quick things to check if a call to your UIFN isn't connecting.

Key characteristics of a UIFN

• One number worldwide — your UIFN looks the same everywhere (for example, 800 1234 5678), making it easy to print on marketing materials, business cards, and websites for a global audience.
• Standard dialing format — callers dial their country's international access code (such as 00, 011, or +), followed by 800 and your 8-digit number. For example: 00 800 1234 5678.
• Free for the caller — like other toll-free numbers, the cost of the call is covered by your business, not the person calling.
• Coverage varies by country — a UIFN must be activated in each country you want to reach. It's normal for a number to be live in some countries and still being set up in others.
• Mobile support is best-effort — landline calls to a UIFN are generally reliable, but not every mobile carrier supports routing +800 calls, so mobile connectivity can vary by network.

Quick checks if your UIFN call isn't connecting

Most connection issues come down to how the number was dialed rather than a problem with the number itself. Before reaching out to support, it can help to check the following:

1. Confirm the exact dialing sequence

Make sure the caller used their country's international access code, not a domestic toll-free prefix. A common mistake is dialing 0 800 instead of 00 800 — this small difference can send the call to the wrong place or cause it to fail entirely.

[Find more information on access codes here: https://support.avoxi.com/99507-number-registration/uifn-access-codes?from_search=236772663]

2. Try a landline if the caller is on mobile

Some mobile carriers don't support +800 call routing. If the caller is on a mobile phone and the call won't go through, ask them to try a landline if one is available — this helps confirm whether the issue is carrier-related.

3. Still no luck? Reach out to AVOXI Support

If dialing looks correct and the issue continues on a landline, our support team can check your number's activation status and coverage for that country and help you from there.

What to include when you contact support

Having a few details ready helps us resolve the issue faster:

• The exact number and sequence that was dialed
• The caller's country
• Whether the call was made from a mobile phone or a landline, and the carrier if known
• The date and time of the failed call

Our team is happy to help you get your global number working exactly the way your business needs it to.