Lock screen widgets are genuinely useful and they are also the most common way an iPhone leaks information to someone who has not unlocked it. They sit under the clock, they update themselves, and they are visible to anyone who picks the phone up or looks at it on a desk.
Most people add them once and never think about what is on display. Here is what to check.
What a locked phone is showing right now
Pick up your phone, do not unlock it, and read the screen as a stranger would.
The calendar widget can show your next event's title and location. The weather widget shows the city you are in. A reminders widget shows the text of the next reminder. A fitness widget shows your activity. A stocks widget shows what you hold.
None of that requires the passcode. It is on the outside of the phone.
Whether any of it matters depends entirely on the content. "Dentist, 3pm" is harmless. A calendar entry with a client name, an address, or a personal medical appointment is a different thing, and it is visible to anyone at the table.
The widgets worth thinking twice about
Calendar. The biggest single source, because event titles are written for you and not for an audience. A "Next event" widget will show whatever you called it.
Reminders. Same problem, often worse, because reminders are written more casually than calendar entries.
Home. Shows the state of your home accessories and, depending on configuration, lets some of them be controlled without unlocking. Check Settings, Home, and whether accessory control is allowed when locked.
Find My. Can display the location of people who share with you.
Any third-party widget. Messaging, email and note apps sometimes surface content in a widget that they would not show in a notification preview, because the two are configured separately.
The widget nobody thinks of
The clock itself, in the versions that show more than the time.
Some clock styles and the date line above it carry information you did not choose to display. More to the point, so does everything else iOS puts on a locked screen without calling it a widget: the Now Playing panel showing what you are listening to, the live activity for a delivery or a journey showing an address, and the notification stack itself.
Live Activities are the most overlooked of these. A food delivery, a ride, a flight or a sports score can sit on the lock screen in full, updating, for as long as the activity runs. They are controlled per app under Settings, then that app, and there is a general switch under Settings, Face ID and Passcode for what is accessible when locked.
That same settings screen is worth reading in full once. Under Allow Access When Locked you can turn off Today View, Notification Centre, Control Centre, Siri, Wallet and Reply with Message. Each one is a small opening, and most people have never looked at the list.
The settings that control it
Two separate places, which is why this is easy to get wrong.
Widgets themselves are edited from the lock screen: touch and hold while unlocked, tap Customise, choose the lock screen, then tap the widget area to add or remove.
What appears in notifications is separate, under Settings, Notifications, Show Previews. Setting that to When Unlocked is the single most useful change most people can make, and it does not affect widgets at all.
The Home accessory permission is in a third place, under Settings, Home.
Decide per widget, not all or nothing
The instinct after reading a list like this is to remove every widget, and that is usually the wrong response — you lose real convenience to guard against a risk that may not apply to you. Go the other way. Look at what each widget is actually displaying on your phone today, then keep the ones whose content is harmless and drop the ones whose content is not. A weather widget is fine for almost everyone. A calendar widget is fine for some people and not for others, and the difference is what you write in your calendar, not what the widget does.
The depth effect trade
Worth knowing because it catches people out. Adding any widget under the clock disables the depth effect on that lock screen, which is the feature that lifts the subject of a photo in front of the time.
So a lock screen is effectively either a picture with depth or a picture with widgets, and you choose per screen. If you want both, build two lock screens and attach them to different Focus modes.
A middle path with Focus modes
The useful arrangement, if the content varies by context, is to have more than one lock screen.
A default screen with the widgets you want in private, and a second screen with none, attached to a Focus you trigger when you are somewhere public. The phone changes appearance and stops displaying anything when you switch.
Touch and hold the lock screen while unlocked, tap plus to add a screen, and use the Focus control in the editor to attach one.
Quick answers
Do widgets update while the phone is locked?
Yes. That is the point of them, and it is also why the content on display is current rather than whatever was there when you last unlocked.
Does a Focus mode hide widgets?
Not by itself. A Focus can switch you to a different lock screen, and that screen can have no widgets. The Focus does not blank the widgets on a screen that has them.
What about the always-on display?
On Pro models from iPhone 14 onward, the widgets stay visible in the dimmed always-on state, which means they are on show for far longer than a normal lock screen. Worth factoring in if you leave the phone face up on a desk.
Is a warning wallpaper an alternative to this?
No, they do different jobs. A wallpaper speaks to a person; these settings control what the phone displays. Both are worth having and neither substitutes for the other.
Where to get it
Once the widget question is settled, the wallpaper is a free choice again. DON'T Touch Phone Wallpapers previews each design in a phone-shaped frame, which is also the quickest way to see how much room a widget row leaves.
Read your own lock screen as a stranger once. It takes ten seconds and it usually changes something.