UPI links, automatic reminders, and the MSMED 45-day rule that gives registered suppliers statutory interest when an invoice goes past due.
Late payment is rarely about the client being unwilling. It is about the invoice being one of forty things in someone's inbox, and paying it requiring a bank transfer nobody has time to set up. Most of the fix is friction removal, and the rest is a schedule you do not have to think about.
Every Retainer invoice carries a UPI link and a payment page. On a phone that is two taps, and the "can you share your bank details" thread never happens. The invoice also stays viewable as a link, so a forwarded copy still works for whoever in their team actually pays it.
Retainer sends payment reminders on a schedule as invoices approach and pass their due date. This is worth more than the time it saves: a reminder from a system is a routine process, and the same reminder typed by you at 11pm reads as a relationship problem. Removing the awkwardness is the point.
Under the MSMED Act, 2006, payment to a registered micro or small enterprise is due within the agreed term, capped at 45 days from acceptance. A contract term longer than that is void to the extent it exceeds the cap. Past the appointed day, interest runs at three times the RBI bank rate, compounded monthly, and it is payable whether or not you asked for it.
Since April 2024, Section 43B(h) of the Income Tax Act has given this teeth in a way it previously lacked: a buyer cannot claim the deduction for an unpaid MSME supplier's invoice until it is actually paid. If you are Udyam-registered, a delayed payment is no longer only your cash-flow problem, it is their tax problem, and that changes the conversation.
Retainer computes MSMED interest from the invoice dates so you know the number before you decide whether to raise it. Whether to charge it is a commercial judgement about the relationship, and usually the useful part is knowing where you stand rather than the invoice you send.
An advance. A payment schedule written into the signed contract, with dates rather than milestones open to interpretation. And invoicing the day the milestone is met, not at month end, because the clock only starts when the invoice is issued.