There are two tax credits – child tax credit and working tax credit. You can claim one or both of them, depending on your household circumstances.
Working tax credit is paid to people who work and are on a low income – it does not matter whether you are an employee or self-employed, and you do not need to have children. Child tax credit is paid to people who have children. It is paid in addition to child benefit and you do not have to be working to get it.
Tax credits are administered by HM Revenue & Customs.
New regulations (1 November 2019): Social Security, Child Benefit and Child Tax Credit (Amendment) (EU Exit) Regulations 2019 (SI.No.1431/2019) - New legislation issued that amends social security and tax credit regulations to protect the rights of certain third country nationals to reflect the UK's transition from association agreements to trade and partnership agreements (TPAs) after it exits from the EU >> More tax credit legislation
New Upper Tribunal decision (17 October 2019): CTC/2494/2018 - Actual profitability and a certain level of regular financial transactions are not essential to the definition of "self-employed" for the purposes of entitlement to working tax credit. The case involves the interaction between a s16 decision which had been followed by a s18 decision and reflects on the findings in both  AACR 2  AACR 2ws and CTC/283/2018 >> More tax credit case law
New Upper Tribunal decision (2 May 2019): CTC/2349/2018 - Tax credit - Claim by married woman as a single person - Whether separated in circumstances such that separation likely to be permanent (TCA 2002 s.3(5A)(a)) - FTT direction addressed to claimant that husband attend as a witness - Adverse inference drawn when husband failed to attend - Importance of assessing evidence in its cultural context - Attitudes towards separation and divorce within a Muslim community where married couple also first cousins >> More tax credit case law
New Upper Tribunal decision (30 April 2019): CSTC/283/2018 - Working tax credit - definition of "self-employed" in the Working Tax Credit (Entitlement and Maximum Rate) Regulations 2002 - relevance of profitability and "genuine and effective" in the test of carrying on a trade, profession or occupation "on a commercial basis" - circumstances in which the Upper Tribunal will hear an appeal against a decision of the First-tier Tribunal in a case which challenges a decision under Section 16 of the Tax Credits Act 2002 when a Section 18 decision has subsequently been issued >> More tax credit case law
New regulations (16 April 2019): Child Benefit and Child Tax Credit (Amendment) (EU Exit) Regulations 2019 (SI.No.867/2019) - New regulations issued in relation to child benefit and child tax credit for those granted leave to enter or remain under the EU Settlement Scheme >> More tax credit legislation
New Upper Tribunal decision (11 April 2019): CTC/2376/2017 - A decision taken by the HMRC not to award a tax credit under section 14 of the Tax Credits Act 2002 cannot be followed by a final decision under section 18 of the 2002 Act. Therefore, no section 18 decision may cause an appeal to the First-tier Tribunal against such a decision to lapse. To the extent that a three-judge panel of the Upper Tribunal in LS & RS v HMRC  AACR 2;  UKUT 0247 (AAC) expressed the contrary view, its comments were obiter and should not be followed >> More tax credit case law