I’m a frequent reader of SitePoint Forums (my username is dnordstrom). In a recent discussion the poster is wondering if he can, and should, take a client’s website down due to overdue invoices. This article will express my view on this all too frequent issue.
Ethics
Ethics are important. However, this is not a question of ethics. It stopped being a question of ethics when the client after repeated reminders and unanswered inquires decided to postpone payment beyond the due date. Regardless of the circumstances, this is an unethical thing to do.
One may say that the client is excused if they are having financial problems. If the client would have actually taken the forum poster’s calls or replied to his repeated inquires, it would have been an entirely different story. Financial problems are no excuse to skip payments but if the client communicates her concerns, a contracted professional may decide to cut her some slack. Of course, sympathy is impossible without communication.

Patience
How far overdue is the invoice and what are the terms? How much do you need the money? This is not only a question regarding your client’s situation but also yours. If you have a financial buffer for these situations, which you should have but which is not always realistic, you may be able to afford being patient for a while longer.
On the other hand, if you’re in desperate need of this payment to be able to eat and pay the rent, there is no question about it.—you obviously need to take care of it immediately. Don’t use up your credit or borrow money because your client is an ass.
Another thing you may want to consider is the terms of the invoice. If you’re using NET15 payment, the client may have been expecting twice as much time to pay the invoice. Again, if the client communicates her concerns we can surely come to an acceptable agreement. Due to the frequency of overdue payments in this industry, NET15 could be a smart move as long as the client is aware of the terms from the start and accepts them. 30 days however is more common and should be fine with any client, in an ideal world.
Inform
This leads us to the matter of keeping everyone informed. It’s your job to make sure that the client knows when the project is delivered as well as when the invoice is both sent and due, preferably far in advance. Agree on the payment terms before both of you sign any contract or you risk conflicts once the project is completed.
Charging an up-front fee can be a good thing for keeping the client dedicated and getting her to listen and understand the terms of the payments. You’ll also be able to handle expenses during the project and be more certain that the client actually has money to pay for your work. For up-front payments to be useful, they should in my opinion be applied to larger projects. For minor work it’s just ridiculous and you risk appearing like a jerk.
Once you send the invoice, make sure the client gets it and that they are informed about the due date. As the due date is closing in, send out reminders. On or around the due date, send another reminder and a personal message asking if there’s any way you can help with the payment. Always remain polite and professional.
FreshBooks and Billings are great invoicing applications that I recommend. Freshbooks for example will automatically send out reminders after a certain amount of days which you can configure to your liking.
Future
Consider your future with this client. A core part of my business concept is to nurture valuable and friendly long-term relationships with my clients. Even though you have done everything right and you are entitled to the payment (two weeks ago), some ways of dealing with this issue could piss off your client and potentially ruin any chances for repeat-business.
Then again, do you really want to continue working with a client that doesn’t pay on time or even reply to your inquires about the payment? This client is practically waving a huge red flag right in your face. However, use your intuition. If you feel that this is a one-time occurrence, make it work. If you have a bad feeling about the client, grab your money and get out.

Contract
You have a solid contract, right? Having a contract is a necessity. Keeping this paragraph relevant to the situation, the contract should include who owns the rights to the work, when those rights are transferred, terms of payment, what happens upon overdue payment, any late fees you may charge, and terms of cancellation and termination of the contract.
Of course, your quotation or proposal should also state clearly the scope of the project so that everyone is aware of what the term “complete” means. Being ridiculously detailed can save you a lot of trouble during the project since people tend to misunderstand the information in this kind of paperwork. If you need to use very technical terms, also explain them practically.
What to do
The original question was if you could take the website down. If you have a contract stating that the work belongs to you until payment has been received, you can definitely take it down. If you are hosting the site yourself then of course you can take it down. Make sure you give plenty of notice before doing so though.
If you’re hosting the site yourself and want to receive the payment fast, you can replace the website with a notice that the “account has been suspended due to overdue payments” or similar. Turn on your evil asshole mode and be creative. Don’t do this if you value your relationship with the client.
Have patience—don’t immediately take the website down even though you want to. Remain professional, positive and courteous at all times. As mentioned, inform the client that the invoice is overdue and ask if there is anything you can do to help. This makes you a service-minded professional rather than some jerk screaming “SHOW ME THE MONEY”.
As a user on the forums states, you can offer a down-payment option to relieve some of the pressure that is keeping the client from paying. The same user recommends that the agreement includes that if the down-payments become overdue, the whole remaining amount will be charged immediately.
If you after repeated phone calls and emails cannot get an answer about what’s going on and the invoice is way overdue, you’ll need to take action. While it may seem harsh, send the client a new invoice with a late fee applied and inform her that you would rather avoid taking legal action. It would perhaps be more subtle to take the website down, depending on how much that would interrupt the client’s business.
Conclusion
Don’t be a pussy. Consider these things and if it seems like the rational choice, take the site down and stop delivering. Clients need to learn that due dates are set for a reason and ignoring them without notice is unacceptable. But remember to be polite and behave professionally and positively regardless of the situation.