Can an employer require you to use a personal credit card to purchase items for the workplace?
This question is not about personal travel or meals or the like, but rather items that are purchased for use by the entire workforce and customers (not just the individual employee). Can the workplace require the employee to pay for these with a personal credit card and then seek reimbursement after the fact? An optional solution for this same matter might be the creation of a petty cash fund to be used for such purchases, instead of the employee's personal credit card.
It is absolutely ok--and indeed, quite common, especially in smaller companies--to have employees purchase work supplies (either common or company ones, or for their own use) and then seek reimbursement. You are right that a petty cash fund is one solution, as would be having a company credit card, establishing an account at the company's main vendors, getting a check cut for the purchase, using a gift card or prepaid debit card the company sets up, etc. And those other methods do offer some advantages over employee purchase and reimbursement. However, such because there are other, or even better ways, to do this, does not mean that a company cannot have an employee make purchases and then reimburse him or her. Conceptually and legally, there is no difference from an employee buying reams of copy paper on his or her own card vs. purchasing air fare for a business trip.