Rebalancing Trigger: Drift-Based vs Calendar, Which Fits You?

Your allocation has drifted from target and now you are wondering how often to drag it back. This helps you choose between a drift-based trigger, rebalance when an asset class wanders past a set threshold, and a calendar approach like quarterly or annual, using your target, current drift and horizon. You get the trade-offs in cost, effort and discipline. For hands-on investors setting a rule they will actually keep.

I have a target asset allocation of {TARGET_ALLOCATION} (e.g. 60% equities, 30% bonds, 10% alternatives). My current allocation has drifted to {CURRENT_ALLOCATION}. Help me decide whether a drift-based rebalancing trigger (e.g. rebalance when any asset class moves more than {DRIFT_THRESHOLD}% from target) or a calendar-based approach (e.g. quarterly or annually) is better suited to my situation. My investment horizon is {TIME_HORIZON} years and I am in a {TAX_WRAPPER} account. Factor in transaction costs, tax implications of selling, and the behavioural risks of each approach. Give me a clear recommendation with reasoning.