Part-year FBAR

The following appears on FBAR forms:
   This report is for calendar year ended 12/31 xxxx.

I'll need to file a part-year FBAR for 2015 due to my renunciation today – is it necessary to indicate that it’s not for the full year?

Or it it advisable to include the whole year even though non-US persons don't have to file?

Good question, the answer to which I too would like to know.  There's a discussion at http://isaacbrocksociety.ca/expat_tax/comment-page-92/ with some reports of what various people have done.

As the FBAR comes into play if you go over the $10,000 for even one day, I would have thought that it doesn't matter whether you fall under it for the full year or not.

The IRS states that FBARs have to be completed only by US Persons. The assumption is that someone is a US Person for the entire calendar year - there are no references to partial years.

After reading through the comments in the above link (thanks iota), it seems the decision on how to report is left up to you (or your accountant if you have one).

For me, it makes sense to only include balances up to my renunciation date since I can't be considered to be a US Person after that date. I'll also avoid opening any new accounts until 2016.

I've just found this good link which nicely illustrates the confusion surrounding this issue:
http://hodgen.com/fbar-filing-in-the-year-of-expatriation/

Phil Hodgen's advice is to provide the account information for the full year regardless of your expatriation date.

Thanks for the link.