Bitrix24 Standard or Professional plans subscribers can add own company's logo to the Bitrix24 account. This option can be found under Settings in the left-sided menu:
Please note that only your Bitrix24 account administrators have access to the Settings page.
Use "upload logo" tab under Company Logo section. Please note that the maximum file dimensions should not exceed 222px by 55px.
Remember that you can always delete logo and upload a new one if necessary.
The uploaded file will be displayed as your company's logo in the left top corner for all Bitrix24 account users.