The date acquired of a short sale is the date you closed the short sale. A short sale is closed when you go to the market and acquire securities to replace the borrowed ones. The date of sale/disposal is the same date if you closed at a profit.
@fanfare provides additional details below:
I have desktop deluxe, I have no problem entering a short sale using the date opened as the sales date and the date closed as the date acquired.
that's the way my broker reports them
what's more, I import the trades and I get no red flags in Turbotax except when the cost basis is left bland (option expired)
The thing is, not all brokerages supply you a 1099-B according to IRS requirements,
TD Ameritrade, for one, reports a short sale as described, above.
Some brokers will make date disposed equal to date acquired.
If your gain/loss totals are accurate, and TurboTax passes it, I expect you can file that way.
References:
IRS Instructions for Form 8949,
"Column (c)—Date Sold or Disposed Of
Enter in this column the date you sold or
disposed of the property.
"For a short sale, enter the date you delivered
the property to the broker or lender to
close the short sale."
That would be the settlement date after acquiring the property.