Bought a home in 2016. Put property taxes in escrow at closing but didn't get seller credit at close because he was disabled vet. Can I claim as extra home expense?

Yes, you would deduct the amount that you paid. If the seller did not give you a credit at closing and you had to pay the whole year, enter the entire amount.

Per IRS Publication 17 Chapter 22, page 153:  Division of real estate taxes between buyers and sellers.

• If you bought or sold real estate during the year, the real estate taxes must be divided between the buyer and the seller.
• The buyer and the seller must divide the real estate taxes according to the number of days in the real property tax year (the period to which the tax is imposed relates) that each owned the property.
• The seller is treated as paying the taxes up to, but not including, the date of sale.
• The buyer is treated as paying the taxes beginning with the date of sale. This applies regardless of the lien dates under local law.

Related information:

• Where do I enter the real estate taxes I paid?
• Can I deduct real estate tax?
• Where can I find out how much real estate tax I paid?