As a building labour I have to buy tools for my job ,how do I claim this or can I

Hi there! You can deduct certain expenses (including any GST/HST) you paid to earn employment income. You can do this only if your employment contract required you to pay the expenses and you did not receive an allowance for them, or the allowance you received is included in your income. 

If you are employed, then you will need a signed T2200 from your employer in order to claim any employment expenses: https://www.canada.ca/en/revenue-agency/services/tax/individuals/topics/about-your-tax-return/tax-return/completing-a-tax-return/deductions-credits-expenses/line-22900-other-employment-expenses.html 

Hey! I think I can help with this one. Even if you work for another employer, you can claim tools purchased. Here is the information from the Government of Canada on how to do that: https://www.canada.ca/en/revenue-agency/services/tax/individuals/topics/about-your-tax-return/tax-return/completing-a-tax-return/deductions-credits-expenses/line-22900-other-employment-expenses/employed-tradespersons-including-apprentice-mechanics/deduction-tools-tradespersons.html

Hello, we appreciate your question. Your expenses can be eligible for deduction as "tradesperson tools expenses". Please review CRA guidance. To make the claim, review the employment expense details (T777) page to make the appropriate entry. 

Furthermore, do you have a signed T2200 declaration form from your employer? Should the CRA elect to review these expenses they will likely ask for this document.