Even when your iPhone is on silent mode, incoming calls and notifications will cause your phone to vibrate. To avoid this, turn off Vibrate in Silent Mode or use Do Not Disturb instead. Learn how to change the vibration settings, and how to use Do Not Disturb and System Haptics (the vibrations that respond when you touch iPhone 7) on a handset without vibrations.
Steps
Method 1 of 6: Disabling vibrate on an iPhone 7

Step #1. Open your iPhone's home screen
Vibration can be turned off in the Settings app on your home screen.

Step #2. Press the Settings app

Step 3. Tap on 'Sound and Haptics'

Step #4. Hit the green "Vibrate on call" switch
Do this if you don't want the iPhone to vibrate in normal (not silent) mode. The switch will turn gray (off).
If the switch was already off/gray, then the phone was not set to vibrate for notifications

Step 5. Press the green "Vibrate in silent mode" switch
Do this if you want to prevent your phone from vibrating in silent mode. The switch will turn gray (off).
If the switch was already off/gray, then the phone was not set to vibrate in silent mode

Step 6. Press the Start button
Your settings take effect immediately.
Flip the switches back to On at any time to enable vibrations
Method 2 of 6: Disabling vibrate on an iPhone 6 and older

Step #1. Open your iPhone's home screen
Vibration can be turned off in the Settings app on your home screen.
If you want to quickly turn off 'all' notifications (including vibrations), such as when you're in a meeting, check out the section on Using Do Not Disturb

Step #2. Press the Settings app

Step 3. Tap on 'Sounds'

Step #4. Hit the green "Vibrate on call" switch
Do this if you don't want the iPhone to vibrate in normal (not silent) mode. The switch will turn gray (off).
If the switch was already off/gray, then the phone was not set to vibrate for notifications

Step 5. Hit the green "Vibrate in silent mode" switch
Do this if you want to prevent your phone from vibrating in silent mode. The switch will turn gray (off).
If the switch was already off/gray, then the phone was not set to vibrate in silent mode

Step 6. Press the Start key
Your new settings will take effect immediately.
Flip the switches back to On at any time to enable vibrations
Method 3 of 6: Use Do Not Disturb on iOS 7 and later

Step #1. Open your iPhone's home screen
A quick way to turn off all vibrations is to set your phone to Do Not Disturb. To turn off vibrations even when your screen is active, see Turn off vibrations on iPhone 7.
In this mode, the phone will not light up, vibrate or make sounds when the screen is locked

Step 2. Swipe from bottom to top
This will open the Control Center.

Step 3. Tap the moon icon
The icon will turn blue and a smaller moon icon will appear at the top of the screen in the status bar. This means that Do Not Disturb mode is enabled.
To turn off Do Not Disturb mode, swipe up from the home screen and tap the moon icon again
Method 4 of 6: Using Do Not Disturb on iOS 6 and older

Step #1. Open your iPhone's home screen
A quick way to turn off all vibrations is to set your phone to Do Not Disturb. To turn off vibrations even when your screen is active, see Turn off vibrations on iPhone 6 and older.
In this mode, the phone will not light up, vibrate or make sounds when the screen is locked

Step #2. Press the Settings app

Step 3. Turn on the "Do Not Disturb" switch
When the switch turns green, a small moon icon will appear at the top of the screen in the status bar. This means that Do Not Disturb mode is enabled.

Step #4. Turn off the "Do Not Disturb" switch
When the switch is gray, the moon icon will disappear and you will receive notifications (and vibrations) again.
Method 5 of 6: Disable System Haptics on iPhone 7

Step #1. Open your iPhone's home screen
If you don't like the vibrations when you press and swipe on your iPhone 7, you can turn them off in the Sound and Haptics settings.

Step #2. Press the Settings app

Step 3. Tap on 'Sound and Haptics'

Step #4. Hit the "System Haptics" switch
You have to scroll down to find this. When the switch is in the Off (grey) position, you will not feel any haptic feedback.
Your phone will continue to vibrate for calls and notifications unless you turn off all vibrations
Method 6 of 6: Disable Emergency Vibrations (All iPhones)

Step #1. Open Settings app
This is the gray icon with gears.

Step #2. Press General

Step #3. Tap on Accessibility

Step #4. Press Vibrate

Step 5. Hit the switch next to "Vibrate"
Make sure no green appears. All vibrations are now disabled for your iPhone.