List of Income Tax Circulars issued by Central Board of Direct Taxes (CBDT) during 2021, clarifying/ amending provisions of Income Tax Act/ Rules:

List of CBDT Income Tax Circulars 2021 (No./ Date/ Particulars)
CBDT Income Tax Circular 17/2021 dt. 09/09/2021: CBDT further extends due dates for filing of Income Tax Return (ITR)/ Tax Audit Report (TAR)/ Transfer Pricing Report (TPR), in respect of FY 2020-21/ AY 2021-22, in view of difficulties reported by the taxpayers and other stakeholders in e-filing thereof at the portal.
CBDT Income Tax Circular 16/2021 dt. 29/08/2021: Extension of time lines for electronic filing of various Forms under the Income-tax Act, 1961.
CBDT Income Tax Circular 15/2021 dt. 03/08/2021: CBDT further extends due dates for e-filing of various Forms under the Income-tax Act, 1961, in view of difficulties being faced/ reported by the taxpayers and other stakeholders. Read More
CBDT Income Tax Circular 14/2021 dt. 02/07/2021: CBDT Guidelines for removal of difficulties in relation to deeming provisions of Sections 9B (Income on receipt of capital asset or stock in trade by specified person from specified entity) and Section 45(4) (Capital Gains) of the Income-tax act, 1961.
CBDT Income Tax Circular 13/2021 dt. 30/06/2021: CBDT has issued Guidelines for removal of difficulties in implementation of provisions relating to TDS on Purchase of Goods u/s 194Q, including TDS provisions on e-commerce operators u/s 194O and TCS provisions u/s 206C(1H), applicable w.e.f. 01/07/2021. These guidelines clarifies various issues as under:
(1) Applicability on transactions carried through various Exchanges;
(2) Calculation of threshold for the financial year 2021-22;
(3) Adjustment for GST, purchase returns;
(4) Whether non-resident can be buyer under section 194Q of the Act;
(5) Whether tax is to be deducted when the seller is a person whose income is exempt;
(6) Whether tax is to be deducted on advance payment;
(7) Whether provisions of section 194Q of the Act shall apply to buyer in the year of Incorporation;
(8) Whether provisions of section 194Q of the Act shall apply to buyer if the turnover from business is 10 crore or less;
(9) Cross application of section 194O, sub-section (1H) of section 206C and section 194Q of the Act, etc.
CBDT Income Tax Circular 12/2021 dt. 25/06/2021: CBDT extends timelines for various compliances under Income Tax  to provide relief to taxpayers in view of the severe pandemic COVID 19.
CBDT Income Tax Circular 11/2021 dt. 21/06/2021: CBDT clarifications on use of functionality for Compliance Check u/s 206AB and 206CCA of the Income-tax Act, 1961, w.e.f. 01/07/2021, for tax deductors and collectors. Also please refer CBDT Income Tax Notification 1/2021 DIT Systems dt. 22/06/2021 and CBDT Income Tax Order dt. 21/06/2021 dt. 21/06/2021, in this regard. 
CBDT Income Tax Circular 10/2021 dt. 25/05/2021: CBDT Clarification on limitation time for filing of Income Tax Appeals before the CIT (Appeals).
CBDT Income Tax Circular 9/2021 dt. 20/05/2021: CBDT extends certain Income Tax compliance timelines including for filing of Income Tax Return (ITR)/ Tax Audit Report (TAR)/ Transfer Pricing Report (TPR), in respect of FY 2020-21/ AY 2021-22, for providing relief to taxpayers/ professionals in view of spread of COVID-19 pandemic. Also refer:
ITR & TAR Due Dates Extended
CBDT Income Tax Circular 8/2021 dt. 30/04/2021: CBDT extends certain Income Tax compliance timelines as relief to taxpayers in view of the severe spread of pandemic COVID 19.
CBDT Income Tax Circular 7/2021 dt. 26/03/2021: CBDT condones the delay in filing of Form No. 10B for years prior to AY 2018-19 u/s 119(2)(b) of the Income-tax Act, 1961.
CBDT Income Tax Circular 6/2021 dt. 26/03/2021: CBDT condones the delay in filing of Form No. 10BB for AY 2016-17 and subsequent years u/s 119(2)(b) of the Income-tax Act, 1961.
CBDT Income Tax Circular 5/2021 dt. 25/03/2021: CBDT Order further defers the reporting requirements relating to Clauses 30C (GAAR)/ 44 (GST) of revised Tax Audit Report Form 3CD, upto 31/03/2022, in view of COVID 19 pandemic. Read More
CBDT Income Tax Circular 4/2021 dt. 23/03/2021: CBDT Clarifications on provisions of the Direct Tax Vivad se Vishwas Act, 2020, regarding classification of a case as a ‘search case’.
CBDT Income Tax Circular 3/2021 dt. 04/03/2021: CBDT clarification u/s 10 of the Direct Tax Vivad se Vishwas Act, 2020.
CBDT Income Tax Circular 2/2021 dt. 03/03/2021: CBDT clarification on Residential status of certain individuals under Income-tax Act, 1961 and COVID 19 pandemic. 
CBDT Income Tax Circular 1/2021 dt. 15/01/2021: CBDT has clarified the issue of amount of fund managers remuneration prescribed under section 9A(3)(m) of the Income Tax Act, 1961.
CBDT Updates (Income Tax)
Income Tax Circulars, Instructions, Notifications, Orders, Press Releases, etc. issued by the Central Board of Direct Taxes (CBDT) in different years:
CBDT Circulars: 2021, 2020, 2019, 2018, 2017, 2016, 2015
CBDT Instructions: 2021, 2020, 2019, 2018, 2017, 2016, 2015
CBDT Notifications: 2021, 2020, 2019, 2018, 2017, 2016, 2015
CBDT Orders: 2021, 2020, 2019, 2018, 2017
CBDT Press Releases: 2021, 2020, 2019, 2018, 2017, 2016, 2015
Note: For Official/ updated copy, please visit the Income Tax Deptt. website.