How do I turn off read receipts on WhatsApp so people can't see the blue ticks?

Settings > Privacy > toggle off 'Read receipts'. Now people won't see blue ticks from you, but the catch is it's mutual: you also stop seeing when others have read YOUR messages. Two things it does NOT affect: group chats still show read receipts no matter what (you can't turn those off), and voice notes still show blue ticks once played even with the setting off. If you just want to sneak the odd read, leaving receipts on and reading from the notification shade, without actually opening the chat, is the quieter workaround.

Remember it's a two-way street. Turn off your blue ticks and you lose the ability to see everyone else's too. That trade-off puts a lot of people off doing it.

Read receipts stay ON in group chats regardless of the setting, and voice notes always show a blue mic when played. The toggle only covers one-to-one text messages.