I'm a web designer, I generally just ensure I have some leverage over the client
and they always pay without many issues.

Obvious example - just make it clear that services will be suspended if invoices
aren't paid. Don't let clients owe you too much money where they'd think it
worthwhile to not pay.

We had an instance last year where the client wouldn't pay up after sending
daily reminders for about 3 days. These were personal messages over whatsApp.
Then we sent 2 system generated reminders and then deactivated the account. The
client got pissed but we had the money in our account within 2 hours of
deactivation.

Just deactivate the account after 2 reminders

You don't get an account without paying. If you don't pay, you get deactivated.
Simple enough. Doesn't matter who they are.

Have experience with this working at enterprise level w monthly invoices. We
have a tiered system with 3 reminders (all sent manually) if we’re not getting
any response from main contact or finance contact and 3 monthly invoices are
outstanding well email all users on the account saying “hey, hope you’re all
doing well. Unfortunately we haven’t heard back from X and Y on your outstanding
invoices so we’ll be closing your account on X date, if you’d like to keep
access please email X”

Normally the users will fight to keep account open w finance - hope this helps!

i had the same issue,and just deactivated account. You do not pay,you do not get
the service.

If amount is big you can work with collection agency.

Our clients get an automated email when the payment fails. We also follow up
manually via phone and email. If the client hasn’t responded to any of our email
or calls within 3 working days we stop their plan (ie close to the account). If
the client replies to let us know what’s happening and agree when they will pay,
we’re almost always happy to keep their plan open

Find the conversation. See what's going on. Keep it human. Do set your
boundaries (terms of payment) and have a plan for when you need to upscale your
measurements.

We follow gmail style account suspension and grace period activation. 1 week
grace in our case.. gmail offers 30 days.

Grace is customizable from the backend. We extend grace if we find a genuine
reason.

Violence

2 emails, then call them. Sometimes emails go to spam or the original billing
contact leaves the company. A simple call works it all out most of the time.