Non-deductible IRA's - when do you convert from traditional to Roth IRA?

[nottoolatetostart]

Hi all -

For those that are do a traditional non-deductible IRA and then rollover through the backdoor to a Roth IRA, when do you normally make your traditional IRA contributions? I have been waiting to do it on the last business day of the calendar year (e.g. Dec 30 or 31) and then roll over to Roth on the first calendar day of the new year (Jan 2 or 3). I guess I avoid paying any tax on that money because generally there are no capital gains or interest (so $5500 is rolled over as opposed to $6000 if I did it throughout the year).

Does anyone do it differently?

Thanks!

[arebelspy]

What are you doing with the money in the meantime?

If it's just sitting idle, it may be better to contribute early and just pay taxes on the gains - you end up with more on average.

[gimp]

I'd rather have profit to pay taxes on, than no profit.

[Bourbon]

This was my first year, but I plan to contribute early in the year and re-characterize the next day.  It may not be January 2nd but will be in January sometime.