Here is the page of iTunes UK merchant
iTunes UK
37 Miles per £10

iTunes UK

When will I get my Miles?

PurchaseToday
Tracked within i5 day(s)
Awarded within i105 day(s)
Rewards apply to all paid content.

Stated reward is for iTunes books, TV, movies, iOS in-apps and in-app subscriptions. You will earn a lower reward on purchases of music, playlist or ringtones. Purchases of iTunes Gift Card are not eligible to earn rewards.

You cannot earn rewards for purchasing hardware through the iTunes program or on Donations.

All In-App Purchases made in a 24-hour window in that same app will be eligible to earn rewards.

Your purchase will be shown in your account around 14 working days from the date of your purchase.

iTunes will not entertain missing claims queries.

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Rewards are not calculated on postage / handling / delivery costs or associated purchase taxes in your region (This may include but not be limited to VAT, GST etc).

About iTunes UK

iTunes Store is the entertainment capital of your world. Imagine an entertainment superstore open 24 hours a day, 7 days a week. One that delivers anything you want, instantly. Shop the iTunes Store for music, TV shows, iPod games, audiobooks, free podcasts and more. And you can give as good as you get with iTunes gifts.