Browse Banking

Effective Annual and Percentage Yields

Effective annual rate and yield terms used to compare quoted rates after compounding effects.

Effective annual and percentage yield terms show what a quoted rate means over a year after compounding is included.

Use this branch when comparing deposit yields, loan rates, or interest-bearing products that quote nominal rates, APY, AER, or effective annual rates.

Key Terms in This Branch

TermWhat it compares
Annual Equivalent Rate (AER)An annualized rate that reflects compounding, commonly used for savings-rate comparison in some markets.
Annual Percentage Yield (APY)A U.S. deposit-yield measure that reflects compounding over one year.
Effective Annual RateThe annual rate after compounding effects are included.
Nominal vs Effective RateThe difference between a stated rate and the rate implied after compounding.

Quick Comparison

LabelWatch for
Nominal rateStated rate before compounding adjustment.
Effective annual rateAnnualized rate after compounding.
APY or AERConsumer-facing yield labels that may follow jurisdiction-specific disclosure conventions.

Common Mistakes

  • Ranking accounts by nominal rate when the compounding basis differs.
  • Comparing APY with APR as if both measure the same thing.
  • Ignoring fees, penalties, minimum balances, and introductory periods.
  • Treating a displayed yield as a promise that every depositor will earn that return under all account behavior.

In this section

Choose a subsection first. Deeper term pages live inside each subsection, which keeps large topic hubs readable.

Annual Equivalent Rate (AER)

Annual equivalent rate expresses an annualized return after compounding, commonly used to compare savings and deposit products.

Effective Annual Rate

The effective annual rate converts a nominal rate with compounding into the actual annualized rate earned or paid.

Revised on Sunday, June 21, 2026