A direct account does not require Prime
Hayu’s official app guidance says a viewer can subscribe directly; Amazon Channels is an additional route in selected markets. The presence of Hayu inside Prime Video does not mean every Hayu viewer must first buy Prime.
Identify the actual purchase before choosing an app. A person who signed up directly and someone watching through a hosted channel can begin from different account screens even if they want the same series.
The UK Amazon linking route is specific
Hayu’s support explicitly permits eligible Amazon Channels subscribers in the United Kingdom to link access to Hayu’s own website and apps. The same help says this function is not generally available in other markets.
Follow that genuine linking process where it applies. Do not assume that every hosted channel behaves identically: generic advice saying that cross-app access always works, or never works, would miss Hayu’s stated country-specific rule.
Keep billing with the platform that manages it
Hayu directs partner-platform subscribers to those accounts for billing management. An account link for viewing does not automatically move who collects payment. Keep the original seller and actual subscription confirmation with any payment or cancellation question.
Before creating another subscription, identify whether the current task is linking access, recovering a login or changing the payment arrangement. Those actions should not be treated as the same problem.
Offline viewing belongs to supported mobile apps
The official device page describes downloads on iOS and Android phones and tablets. A television app and a mobile offline copy are different routes. Adding a series to a list does not establish that its episodes are stored for travel.
Use the intended device and episode, then inspect the actual download. For help, name the subscription route, country where linking matters, programme and error without posting account codes. This is more useful than treating every Hayu screen as a universal direct-account or hosted-channel experience.
Questions answered
Can every Amazon Channels subscriber sign into the Hayu app?
Hayu documents a UK linking route; it should not be assumed for every other market.
Does Hayu require Prime?
No. The official page describes direct subscription as well as selected partner options.
Sources & further reading
Official references for the subjects discussed. Service terms and device software can change.