It is a tricky one. As a supplier we have a few people who will not quite pay on time, or need some sort of nudge to convince them to pay on time, and it is very tempting to chase them in advance of being late - i.e. before the due date. When you do that people get quite annoyed - "Of course we will be paying on time". The annoyance is usually because chasing the payment in advance is seen as untrusting and suggesting the customer will pay late. I can't guarantee that our accounts dept have done this, but it is something we try not to do, and would normally only be someone that we really do not trust to pay on time based on a long history of such. Even so, we would have to expect that sort of reaction.
We don't usually have much of a problem because we do charge the statutory late payment penalties that apply when a business customer pays us late. We usually credit the first time, but this is a fully automated process. People learn that at the very least, if they pay late, they get the hassle (trying to get a late payment credited, etc). So they pay on time, or change to direct debit (and so pay on time). It works well.
One trick we did was send a statement mid month if a payment is due. Not a chasing letter or a call, just a statement, what invoices there are and when due and how much. That seems not to cause annoyance, thankfully. It also helps sort any cases where someone has, for some reason, not seen an invoice.
But as a customer, we pay suppliers on time. We are very careful to pay people on time, even the likes of BT where the payment is a very large amount. We plan cash flow carefully to make sure we never pay late. If ever, by mistake, we pay late, we offer to pay the statutory late payment penalties even if the supplier did not know about them. It would be somewhat hypercritical if we did anything different.
Our friends at BT have, however, started getting a tad annoying of late. Some of the BT accounts are complicated because every single month there are a long list of disputes, and also a list of credits where they have agreed previous disputes and deductions are in fact valid. We advise BT clearly of what we dispute and pay the balance on the due date, not a day later. Some of the BT accounts are not a problem, and paid on time, every month, the full amount.
What has got annoying is BT chasing us asking have we paid an invoice, before it is due. This is when the invoice is not due for a week. We always pay on time, but they still ask, every damn month, on several of the BT accounts. And it is starting to wind me up now!
So, am I right? Is it a taboo to chase people for payment before it is due? It is fair that this annoys me?
FYI we asked BT why, and they said that they need to know when we will pay for their forecasts (cash flow, I assume). As the contract does not require us to provide this, I have told them an hourly rate for any future queries of this nature - we'll see what happens.
Of course, to add to the fun, BT have a odd idea on when payment is due. We have 28 days terms, so an invoice issued on 1st is due on 29th. Oddly they state "due on" not "to arrive by" as we would, but when they chase us for payment like this they say that they are expecting payment by 28th. Thankfully the invoice does not say "28 days" but actually states "due on 29th" so not ambiguous at all, but it does just add to the annoyance.
Ironically, whilst it is normal for 28 days from 1st to be 29th, (1+28=29), when we issue invoices we base payment terms on time as well as date, so an invoice issued 09:00:00 on 1st would be due by 09:00:00 on 29th, if on 28 calendar days terms. However, an invoice issued 00:00:00 on 1st (as most are) would be due on or before 23:59:59 on 28th (and we state the date and time clearly). In practice you have to be more than a day late to get penalties, so that is academic, but amused me how something as simple as this can have ambiguities :-)