How did my contacts merge with those on my husbands' iPhone

I suspect your contacts are being synced to your husband's Contacts app because you are sharing an email account. Email accounts come with other data which includes contacts and calendars. It sounds as if he has only recently set up this shared email on his iPhone and perhaps in setting up this email service he also activated the sharing of your contacts which are associated with this email account.

You could investigate this on his iPhone by going into the setting for that account in iOS in Settings > Mail > Accounts [name of email account].

From here you will see the various services you can toggle on or off. If you see that Contacts is active (with a green slider visible) you will have found your culprit.

Do you and your husband share the same Apple ID? If you do, and you both sync contacts with iCloud, they will be the same on both devices. Apple has recommended for more than a decade to NOT share the same Apple ID with someone else.

Read this if you do --> Make sure that each family member has a unique Apple ID - Apple Support

As you can see, not only will contacts be shared, but phone calls and voicemail as well. Plus when you share an Apple ID, you can read each others text messages as well.

leeannefromauburn wrote:

Hello, so we toggled the contacts off but it is stating all yahoo contacts will be removed from your iPhone? Will this delete them from my phone as well? Also- mine is toggled on but I do not have his contacts ?

The alert isn't very nuanced and I infer that it refers to the account with which you are working on the device, not all the other contacts from other sources on the device. Turning off the contact setting should turn off only that account's contacts on that device.

Over on your phone, if this setting on then you are getting the contacts from your email account as it should - these are the same contacts your husband is getting on his device.

But bear in mind the advice given above by lobsterghost1 - that sharing any account isn't best practice and often ends in a muddle, as you are finding out at the moment. lobsterghost1 is referring to an Apple ID account, and although your email seems to be a Yahoo account the principal is the same.

Think through your options and decide if you really need to have the same email account or if you would both be in a better position by having separate email accounts.

This has happened before to me. If he has his ID on your phone, remove it. I had my mom’s ID on my phone, but it synced my contact names with hers, and it messed it all up.