iD Mobile plans are for personal use, not business. Conference calls are not supported.

It's not for business its personal use. ID really isn't good at all. Even lebara and three which it piggybanks off have conference calling

Why would anyone other than a business user want to hold a conference call? Or are you referring to a three-way call?

On an iPhone, dial a number and once the call connects, select “More” and then add people. You should then have the option to merge the call.

A group of friends can all talk to each other at the same time I can't even do 3 way anymore whenever I add a caller it drops the call

When I merge the call it drops. My friend had the same with lebara he called them and they updated his settings howver you can't call ID so how do I get the setting sent to me

I just tested this, and it works for me on an iPhone running iOS 26.3 Beta 3 (Carrier Version 68.0) when used with an eSIM.

To test, I did the following:

1. Dialled our landline (01 number)
2. Pressed ‘More’
3. Pressed ‘Add People’
4. Selected a contact
5. I selected the call contact option and at this point the 01 number was put on hold and the iPhone proceeded to ring contact. 
6. The ‘Merge’ option was displayed once the contact answers the call. I simply selected it!

All three calls connected, and we can now all chat together. It works with WiFi Calling enabled and disabled.

That's very nice but it didn't help me get the answer thanks. 

Hi ​@GHC Thank you for explaining this.When a call disconnects during a 3-way call, it’s usually linked to how the phone is connecting to the network rather than the calling feature itself. As others in the same area aren’t experiencing this, the most important next step is to complete a network settings reset on your device, if you haven’t already done so. This refreshes the network connection and can often resolve call stability and multi-party calling issues.

In the meantime, some users find that using third-party calling or conferencing apps works more reliably, as the phone’s native “merge call” function can occasionally fail when the network connection isn’t stable.Once the network reset is complete, please power the phone off for a few minutes, turn it back on, and then test making a 3-way call again.

~Marquerita