Are HP PAYS Ink plan changes or cancellation effective immediately?

You can choose to make a change to a higher plan effective immediately and retroactively apply to the current billing cycle, or have the upgrade take effect the first day of the next billing cycle.

Changes to a lower plan and cancellation are effective the first day of the next billing cycle. Bear in mind that you cannot downgrade to the Free Printing plan.

For more details, see the HP HP PAYS Ink Terms of Service.