The basics: what "adding a call" means

Adding a call on iPhone means putting your current call on hold and dialing a second person while keeping the first call active in the background. When you add a call, you can switch between the two conversations, merge them into one three-way call, or end one call and return to the other. This feature is called call waiting when it alerts you to an incoming call, and conference calling when you combine multiple calls into one conversation.

Your carrier must support call waiting for this to work — most do, but some older plans or international carriers may not. If you try to add a call and nothing happens, call your carrier to check whether call waiting is turned on for your account.

Key Takeaways

  • To add a call while on an active call, tap the plus sign or "Add Call" button, then dial the new number or select a contact.
  • Your first call automatically goes on hold when you dial the second number, and you can see both calls listed on your screen.
  • You can switch between calls by tapping the name or number of the person you want to talk to.
  • Merging calls into a three-way conversation requires tapping "Merge Calls," and ending one call returns you to the other without dropping both.

Step-by-step: adding a second call

Start with an active call on your iPhone. Look at the bottom of the screen — you will see a plus sign (+) or a button labeled "Add Call." Tap it. Your current call moves to hold automatically, and the keypad appears so you can dial a new number.

Type the phone number you want to call, or tap "Contacts" to find and select someone from your phone's contact list. Once you tap the green call button or the contact name, the second call begins ringing. The first caller hears silence or hold music while they wait.

Your screen now shows both calls. The active call (the one you are currently speaking to) appears at the top in a darker shade or with a "connected" label. The held call appears below it, labeled "on hold." You can see the name or number of both people.

Switching between two calls

While you have two calls active, tap the name or number of the person you want to talk to. The call you tap becomes active, and the other call goes on hold. You can switch back and forth as many times as you need during the same conversation.

If you want to end the call you are currently on and return to the held call, tap the red hang-up button. Only the active call ends — the held call stays connected and becomes active again. This is useful if you need to end a conversation quickly and get back to someone waiting.

Merging calls into a three-way conversation

If you want all three people (you, the first caller, and the second caller) to hear each other in one conversation, look for a "Merge Calls" button on your screen. It usually appears near the bottom, alongside the other call options. Tap it, and the two separate calls combine into a single conference call.

Once merged, you cannot separate the calls again — if you end the call, everyone disconnects. If you need to speak to one person privately again, you must end the conference call and dial them back separately.

When adding a call does not work

If you tap the plus sign and nothing happens, or if the button is grayed out, call waiting may be turned off on your account. Contact your carrier — AT&T, Verizon, T-Mobile, or whoever provides your service — and ask them to turn on call waiting. They can usually do this over the phone in a few minutes.

Some carriers charge a small monthly fee for call waiting, though most include it for free. International calls sometimes do not support call waiting, even if it is turned on for your domestic calls. If you are calling outside the United States, the feature may not be available.

The difference between call waiting and conference calling

Call waiting is the feature that alerts you when someone is trying to reach you while you are already on a call. You see a notification, and you can choose to answer, ignore, or send them to voicemail. If you answer, you now have two active calls and can switch between them.

Conference calling is what happens when you merge those two calls so everyone can hear each other at once. Some people use "conference call" to mean any call with more than two people, whether it started as two separate calls or was set up that way from the beginning.

Frequently Asked Questions

Can I add more than two calls at once?

Most iPhones support up to five calls at the same time, though you can only have one active call at a time — the others stay on hold. You add each call the same way: tap the plus sign, dial the number, and switch between them by tapping each person's name.

What happens if I accidentally hang up on someone?

If you end the active call, the held call stays connected and becomes active. If you end a held call by mistake, that person is disconnected and you stay on the line with the other caller. You would need to dial them back to reconnect.

Do I need a special plan to use call waiting?

Call waiting usually comes with your standard phone plan at no extra cost, but some older or international plans may not include it. Contact your carrier to check. A few carriers charge a small monthly fee, typically $3 to $5, though this is less common now.

Can I add a call if I am on WiFi calling?

Yes, call waiting and adding calls work the same way on WiFi calling as they do on cellular. Your carrier still needs to support the feature, and both calls use your internet connection instead of cell signal.

Why does the screen show "Merge Calls" sometimes but not other times?

The merge option appears only when you have two active calls and your carrier supports conference calling. Some carriers or older plans do not support merging, so the button may not show up even if you have two calls active. You can still switch between them.