Decide which outcome you want
An unwanted email and an unwanted account are different problems. If the aim is simply to stop promotional messages, look for the communication-preference or unsubscribe route described by Sky Free. If the aim is to close the ThreeNow account, account deletion is a separate action. Making that distinction first prevents a small preference change from becoming an unnecessary loss of the login used on household devices.
Use the preference route for messages
Sky Free’s notice describes updating communication preferences through the unsubscribe link in a message or the profile settings on ThreeNow. Start with the message that prompted the change and the account that received it. Changing settings under a different household email can leave the original messages unaffected. Keep any confirmation until the next expected communication so you can tell whether the right subscription to messages was changed.
Treat deletion as a separate account decision
The operator places Delete Account at the bottom of the profile page on ThreeNow web, iOS and Android. Its terms say that once the account is deleted it can no longer access content, although a new account can be created later. Before following that route, check which login is used on the television and whether other household members expect to keep using it. This is an account-level decision, not a method of removing one promotional email.
Do not assume every stored item vanishes instantly
Sky Free says it may retain some information where required by law or for legitimate business purposes. That is a limitation of what the deletion control promises, rather than a reason to speculate about an individual account’s records. For an access, correction or privacy question, use the operator’s current notice and contact route. Record the action you selected and any confirmation, without publishing passwords or personal account details in a public troubleshooting thread.
Questions, answered
Do I need to delete ThreeNow to stop promotional emails?
The operator describes separate unsubscribe and communication-preference controls, so account deletion is not the only route for that aim.
Will a deleted ThreeNow account still play content?
The operator’s terms say the deleted account loses access. A future new account is a separate registration.