Short answer: You can watch IT: Welcome to Derry on Max (HBO Max) in the United States, and through HBO's platforms in other regions where available (with regional streaming partners like Crave in Canada or Sky Atlantic/Now TV in the UK). Availability may vary by country and over time. Details by region

• United States: Max (formerly HBO Max) carries IT: Welcome to Derry. If you’re not already subscribed, you can choose from plans with or without ads, and there are bundling options with other services depending on promotions. HBO also airs the show on a Sunday 9:00 PM ET/PT schedule for traditional TV viewing in sync with the streaming release.
• Canada: Crave hosts the series with episodes released on the same weekend as the U.S. debut; Crave requires a subscription, with geo-blocking outside Canada depending on location.
• United Kingdom: Sky Atlantic premieres the series with streaming available via Now TV or the Sky Go app for subscribers; non-subscribers can consider Sky’s basic bundles or related streaming options.

Additional regional options sometimes include:

• Sky Atlantic/Now TV (UK) for live or on-demand viewing for Sky subscribers.
• Sling TV or Amazon channels as add-ons to access Max content in some markets, or purchasing individual episodes via Prime Video or Apple TV in certain regions.
• Some regions may offer the Max app directly or through local carriers as part of bundles.

What to check before watching

• Confirm your region’s available platforms: Max, HBO, Crave, Sky Atlantic/Now TV, or local equivalents.
• Verify current pricing and whether an ad-supported or ad-free plan is best for you.
• If traveling or outside your home region, be aware of geo-restrictions and consider legitimate access methods offered by your service provider.

If you’d like, tell me your country or region and whether you prefer streaming or traditional TV, and I’ll tailor the exact current options and steps to start watching.