Officiallly:
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You may earn Base point credit for up to two rooms per stay, if all eligible charges for both rooms are paid on one folio. Base point credit will be earned for all eligible folio charges incurred on both rooms. Bonuses issued on Base points or total folio charges, including tier bonuses (15%, 25% or 50%, depending on member tier) and double or triple Base point promotions, will apply to the total Base point credit earned or folio charges incurred for both rooms. For any other bonuses, including HHonors partner bonus points and other promotional bonuses, bonus points will be awarded on one room only. You will receive only one stay credit (including credit toward HHonors VIP tiers), and only one mileage credit will be earned. </font>
Unofficially, I've had four rooms credited to my account by paying for all off them and politely asking the front desk manager for credit.
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On the road, In the air,
I enjoy travel, From here to there.