You need to suspend work because of unpaid invoices.
Overview
When invoices haven’t been paid, it’s not a good idea to continue work. It sets a bad precedent and lets your client know you’re willing to do work for free. When a client says, “the check is in the mail,” don’t assume they’re serious. They may be deflecting and have no intention of paying you.
Hi <Client>,
I’ve enjoyed the work we’ve done together and want to continue our professional relationship, but unfortunately, I have bad news.
Because your previous invoices have not been paid, I’m forced to pause our project.
According to our contract, payment should have been received by <date>.
<detail contract parameters>
We’ve been making significant progress and I’d hate to see us lose momentum.
If circumstances have changed on your end, it would be helpful for me to know the details.
I want to continue the project as planned.
Let me know if I can help.
<You>
Notes & Strategy
It’s in your best interest not to continue without first getting paid.
Client “explanations” at this point should be taken with a grain of salt.
If your client had the means to pay you, they would have done so.
Moving forward, you should set up project milestones with payment coming to you first.
This protects you from repeating the unfortunate situation of having to chase down money from your client.
If it becomes clear your client won’t pay, move on and find better clients.