Exhibit 99.(j)

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in this Post-Effective Amendment to Registration Statement No. 333-191151 on Form N-1A of our report dated December 20, 2023, relating to the financial statements and financial highlights of Calamos Market Neutral Income Fund, Calamos Hedged Equity Fund, Calamos Phineus Long/Short Fund, Calamos Merger Arbitrage Fund, Calamos Convertible Fund, Calamos Global Convertible Fund, Calamos Timpani Small Cap Growth Fund, Calamos Timpani SMID Growth Fund, Calamos Growth Fund, Calamos Growth and Income Fund, Calamos Dividend Growth Fund, Calamos Select Fund, Calamos International Growth Fund, Calamos Evolving World Growth Fund, Calamos Global Equity Fund, Calamos Global Opportunities Fund, Calamos International Small Cap Growth Fund, Calamos Total Return Bond Fund, Calamos High Income Opportunities Fund, and Calamos Short-Term Bond Fund, appearing in the Annual Report on Form N-CSR of Calamos Investment Trust for the year/period ended October 31, 2023, and to the references to us under the headings “Financial Highlights” and “Independent Registered Public Accounting Firm” in the Prospectus and “Independent Registered Public Accounting Firm” in the Statement of Additional Information, which are part of such Registration Statement.

/s/ DELOITTE & TOUCHE LLP

Chicago, Illinois 

February 20, 2024