The message arrives while your phone is face up on the table. The screen lights, and the text sits there in plain view for anyone in the room to read.
Most of the time that is nothing — a delivery update, a group chat. Occasionally it is a bank alert, a verification code, or a sentence from a person you would rather not explain.
iOS gives you fine control over this, and the controls are not hidden. The only real decision is how much glanceability you are willing to trade.
What Show Previews actually changes
A notification has two parts: the fact that something arrived, and the content of it. Show Previews only governs the second. With previews off you still see which app has something new and usually who it is from — you just do not see the text.
The global setting sits at the top of Settings > Notifications, under Show Previews, with three options: Always, When Unlocked, and Never. Whatever you pick becomes the default for every app that has not been given its own answer.
The three options, and who each one suits
Always is the default. Content appears on the lock screen whether or not the phone recognises you. Convenient, and the least private.
When Unlocked is the setting worth defaulting to. The notification arrives collapsed, and the content appears once the phone is unlocked. On Face ID models that happens when you look at the screen, so the text expands in front of you and stays hidden from anyone else at the table.
Never means content only appears after you unlock and open the notification. Stricter, slightly slower, and the right answer if your phone spends time on a shared desk.
Per-app control is where the real answer lives
A single global setting forces one rule onto very different apps. The better approach is a broad default with a few deliberate exceptions.
Go to Settings > Notifications, tap an individual app, and it has its own Show Previews with the same three choices plus Default. Set the global rule to When Unlocked, then walk down the list. Banking, messaging, health, and dating apps can go to Never. A food delivery app or a calendar can stay on Always, because the content is the whole point and none of it is sensitive.
The same screen has Lock Screen, Notification Center, and Banners as separate destinations. Turning off Lock Screen for an app keeps its notifications off that screen entirely while still collecting them in Notification Center.
Verification codes deserve their own decision
Codes sent by SMS land in Messages. With previews on, a code is readable on a locked screen by anyone standing near it, and that is the one preview that can be used against you directly — a code plus a password that leaked somewhere else is a working login.
Setting Messages to Never removes that exposure. Codes still autofill when you are inside a login field, because iOS reads the message itself; you do not need to see it on the lock screen for autofill to offer it.
The places previews still appear
Turning previews off on the lock screen does not cover everything.
Announce Notifications, in Settings > Notifications, has Siri read messages aloud through AirPods, headphones, or CarPlay. Useful while driving, awkward when someone else is listening. It has per-app control in the same screen.
StandBy, on iOS 17 and later when the phone charges on its side, can show notifications on a bedside table. Settings > StandBy has its own toggles, including an option to require a tap before content appears.
An Apple Watch mirrors your iPhone's notifications and has a separate privacy setting in the Watch app under Notifications, controlling whether a notification arrives summarised or in full.
Set the default first, then the exceptions
Change the global Show Previews to When Unlocked before touching anything else, then override only the handful of apps that need a different answer. Every app you install from then on inherits the private setting automatically. Going app by app from a permissive default leaves you fixing it forever, because new apps keep arriving with the old rule.
Keeping the glance without the content
The trade-off is real: previews off means more taps. A few things soften it.
Display As, in Settings > Notifications on iOS 16 and later, offers Count, Stack, or List. Count is the quietest layout and still tells you something arrived. Grouping keeps one line per app rather than a wall of them.
Scheduled Summary batches non-urgent apps into scheduled deliveries you choose, so fewer things light the screen at all. And a Focus mode lets you decide which people and apps break through, which reduces how often a locked screen has anything on it to read.
Quick answers
Will I still know that a message arrived?
Yes. Turning previews off hides the content, not the notification. You still see the app, usually the sender's name, and the time. Only the body of the message is withheld until the phone is unlocked.
Does When Unlocked work without Face ID?
On Touch ID and passcode-only devices, content appears after you actually unlock rather than when you look at the screen. The setting still works; the reveal happens a moment later. On Face ID models it relies on attention detection, so sunglasses or an odd angle can stop the expansion.
Does hiding previews stop someone reading my messages?
Only from the lock screen. Anyone who knows your passcode can unlock the phone and read everything in it. Previews are about the room you are standing in, not about a determined person with your code — that is what the passcode and Stolen Device Protection are for.
Can a wallpaper help here?
Indirectly. A blunt lock screen makes it clear the phone is not communal and discourages the casual pick-up, which is a social effect rather than a technical one. It does not hide notification content. Show Previews does that.
Where to get it
If you want the lock screen to carry a message of its own, DON'T Touch Phone Wallpapers has HD warning and anti-theft designs, from bold text to minimal and funny, plus plain aesthetic backgrounds for when you want the screen quiet. Pick something with a clear area behind the clock so the time and any widgets stay readable.
Set the previews first, then the wallpaper. One controls what is on the screen; the other controls how the screen reads.