Generally, no. When structured correctly, entering a Collar Advance does not trigger an immediate taxable event. You're borrowing against your shares, not selling them, so capital gains taxes are deferred until you eventually settle the contract by delivering shares.
This tax deferral is one of the primary benefits, allowing you to access liquidity now while postponing what could be a substantial tax bill (23.8% to 38% depending on your income and state). However, tax treatment of Collar Advances is complex, and it is important to have qualified tax advisors assisting you with the process.