If you need to hide chat of a particular contact, then you have to chat with him/her from a different whatsapp number. But if you want to hide the contact from your existing Whatsapp, that will not be completely hidden. But still you can check this below method. Please note, I have another unofficial solution for you, which can hide your chat as you asked, so keep reading.
Go to WhatsApp and tap & hold on the chat of the contact you want to hide from others. Now you can see a archive chat logo on top (a down arrow in box).
Click on that. Now you will see the chat is gone from the chat list.
Can’t find the chat? Ok. Go straight to the bottom of all the chats. You will find a option “Archived Chats” there.
Click on that & there you can see the person with all the chats.
But keep in mind that if they send a message to you or you send a message to him/her, it will appear on the normal chat list. But you can achieve the chat again. You can archive a chat as many time as you want. Turning off mobile data or WiFi can help you prevent them sending messages while someone else is watching your GBWhatsApp chats.
Additionally may I suggest you to use a Applock. This can prevent someone to open your WhatsApp without your permission. But still Applocks can be disabled from settings unless the applock is inbuilt. But if someone is watching your chats with your permission, then I think my above trick may work for you.
Now I have another solution for you. This will completely hide your chat with the person.
You have to install GBWhatsApp first. GBWhatsApp is unofficial modded WhatsApp which can be used on any android smartphone. This is not available on Play Store. However you can find many sources of downloading this app by searching Google. Personally I downloaded this from ‘latestmodapks’.
Now login with your mobile number on GBWhatsApp like you do on original WhatsApp. You have to restore the messages first on GBWhatsApp, then you have to log in there. After successful log in, you will see same interface as regular WhatsApp. Now GBWhatsApp has many extra features, in which you can hide a contact as you are trying, you can delete your sent message on the other person’s phone from your phone etc.
So, back to GBWhatsApp. Tap & hold on the chat of the contact you want to hide from others. Now tap on option (three vertical dots). Now you can see an option named “Hide”. Tap that. If it is first time you have to provide a pattern lock as well as a backup question. So now your chat is hidden. Now to access the hidden chat you have to tap on “WhatsApp” on the main screen.
Now unlock the pattern lock and you can see your hidden chats. This chat will be there forever unless you bring the chat back to general chats. Whenever you have to access the hidden chat, you will require to unlock the pattern. So I think this is the most helpful answer you have gotten, unless you don’t want to switch to GBWhatsApp. I put this solution at 2nd because this is not the usual WhatsApp. But personally, I don’t think it is harmful. I use GBWhatsApp personally.
Want to know all the extra features of GBWhatsApp over regular WhatsApp, here is the list I found on internet.
Based on the official & latest version of WhatsApp.
Message auto reply feature – now reply automatically to your contacts when you are busy.
Added new style of chat bubbles, blue ticks.
Added some new groups features for group admins.
Inbuilt DND feature – you can disable internet for WhatsApp only.
Ability to revoke multiple WhatsApp messages at once.
Message Scheduler Inbuilt – Now you can schedule WhatsApp messages
Hide View Status Privacy.
Added option for hiding chats, save status/story.
New Emojis Added.
Video Calling Feature is now working.
Send Videos Up to 50 MB.
Set Group name up to 35 characters.
Fixed Various Bugs while sending videos.
You can hide your last seen, Blue ticks, Second tick, typing status.
Copy status of others on your clipboard.
Make broadcast up to 600 people.
You can put status of 255 characters instead of 139 characters without any issues
About 100+ language supports
Change theme quickly by going into theme option
Mod to stay online for 24 hours
Usable with official as Dual WhatsApp
No ban issues
Create your WhatsApp theme and submit it to GBWhatsApp
Send images up to 90 in one click instead of 10
Ability to copy selected text of WhatsApp
You can also add lock on your WhatsApp without any third party software
You can also change the application icon and notification icon.
Block calls for Specific Contacts.
Send Gif Images, disable voice calling if you want.
Selfie Flash added.
Hide Last Seen for Selected Contacts.
Change ticks|bubbles look style you like.
Media demo without loading, much better than real WhatsApp.
Open links without saving the admin and contact numbers.
Show Online & last Seen on Home.