You can take help of the following links regarding income tax working. 

1)  Forms:- a)  Form 27A (Word/PDF ),16A(Word/Excel)

                 b) Form 16a From Fvu (New) R-2.1 (file size 1.2 mb)

                   (no need to download any software , if any problem, contact , rajiv kumar jain , ph. no . 09896124627)

form 16a is tds certificate for non salary dedecutee

                 c)  Challan TDS 281 (Excel/PDF/Online)                       

                 d)   Printed Barcodes Challan No. 280,281,282,283

                 e)  MDU Income Tax Calcuation Form

                 f)  New Pan/Correction & Duplicate, 49A.zip

                 g)   Know Your Pan/Know Your Tan

                 h)  Form 26AS Registration/View Statement 

                 l)   Section wise Tds Deduction Detail 

                 j)  BSR Codes (All Bank)

                 k)  Challans (TDS/TCS) Status Enquiry

                l)  Name of Pan number verification

                m)   EtdsStructure.zip

2) Calculator:-Income-Tax/Interest 234a,b,c/PPF,NSC,TDS/EMI/

                  House Loan Instalment

3) Track:- Pan&Tan(NSDL)-UTI/E-tds/26AS/Refund of Tax/Challans 

4) Online Payments:- e-TAX/e-TDS/e-LIC 

5) Online Filling:- e-Filling or Direct Login/New Pan/Duplicate Pan 

6) Simple Tax India :- 1,2

7) Planmytax, Mytaxassistant.com

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