Accounts Receivable (A/R) is the balance-sheet asset that tracks money customers owe for products or services already delivered but not yet paid for. It's recorded as a current asset because the company has a legal claim to be paid, and tracked with aging buckets (0-30 days, 31-60, 61-90, 90+) that reveal how quickly customers are actually paying. A/R represents revenue that's been recognized but not yet collected; healthy A/R turns into cash on time; aged A/R becomes collection risk.
The basic mechanics:
Customer signs a $50K contract with Net-30 payment terms. Service is delivered (or in SaaS, the recognized portion is delivered). On the day of invoice: