With itemized deduction, which includes mortgage interest and some amount for property tax, car registration tax. Why turbo tax calculates it as $10000

[DawnC]

Starting in 2018, the SALT deduction (which is either state/local income tax plus property tax OR sales tax plus property tax) is capped at $5,000 for married couples filing separately and $10,000 for all other filers.   Mortgage interest is not part of the SALT deduction.   This TurboTax FAQ explains the limits on mortgage interest, if applicable.  

View your Schedule A to see the details of your itemized deductions.    More information on SALT and other itemized deductions.

How to Maximize your Itemized Deductions

[mahendra-rajput]

Since SALT deductions are capping property tax and other taxes to $10,000 for married filing and if I added $3000 only for property tax, why I am getting full $10,000 credit here as part of itemized deduction.

[MindyB]

Income tax is included in SALT as well.  This would include tax reported on you and your spouse's W-2s in boxes 17 and 19.