When a law firm or a law department launches an online survey, the invitation email should include a projected closing date. “We urge you to take the survey on or before May 31st.” For internal surveys by firms and legal teams, two to three weeks should be sufficient to accommodate holidays as well as employee vacations, illnesses, technical glitches in the hosted software, procrastination, or stretches of high-pressure workloads.

The psychology of setting a date motivates people to put it on their to-do list. Still, quite a few will defer opening the survey until the last day, whereas others will appreciate the flexibility of choosing when to complete the survey.

Under circumstances of uncertainty about how long it will take to collect sufficient responses, you might choose not to publish the due date, but the better practice is to set the timer running and let invitees know. You certainly want to remind them of the approaching due date when you send out reminder emails.

You want to allow enough time so that you obtain questionnaires from a representative portion of the population you invite. Don’t expect fully completed surveys from 100% of the population you reach out to but do strive for reasonably balanced participation among various demographic groups. For example, in a large corporate legal department, you might want at least 70% of all Senior Counsel, Counsel and paralegals in your final data set. As a vendor soliciting survey responses from general counsel, you want to hear from at least a respectable number of participants, such as more than one hundred.
If the deadline arrives and you are still busily cleaning and sending emails to respondents to obtain correct information, slipping past the original closing date won’t adversely affect the survey. Usually, a few laggards will do their part after the official closing time.

Another reason to keep a survey open is that you may have to fix a question or two. Respondents will let you know if there is an ambiguity or question impossible to answer adequately. Also, as you review the early returns, you may spot elements of the survey that need revision. Either situation may justify pushing back the survey close date.

Accordingly, for the reasons touched on above, the law department and the service provider may need to extend the survey’s original deadline. As the day for shutting down collection of survey draws near, you might want to call people who have not yet taken part or visit their offices to prod them (this suggestion applies only if you know the people and their phone numbers, such as in a client satisfaction survey). You might even couple that high-touch encouragement with sending out a second salvo of new invitations if you realize that your overall numbers or your participation among certain groups projects to be inadequate.

Should you publicize the new, later due date? Without a blast email, you might have no way to update recalcitrant invitees. You simply keep waiting longer for more responses. But like selling stock, set the final, final date or the final, final number of responses when you decide to extend.

If you are working with a consultant on the survey project, your statement of work may or may not address an extension of the deadline. Unless payment of a portion of the fee hinges on that deadline, the additional time is unlikely to matter to the consultant.