Upfront payments are the gold standard for cash flow management. A customer pays upfront either fully or partially for the product or service required. There’s no waiting around or complex credit agreements, just cash in the bank.

adverb (of money) paid out at the beginning of a business arrangement

paid before goods are produced or received or services are performed: upfront cost/payment/fee Large upfront costs are incurred to write a complicated piece of software. speaking or behaving in a way which makes intentions and beliefs clear: upfront about sth She's very upfront about why she wants the job.