To calculate the expected return of a portfolio, an investor needs to add up the weighted averages of each of the investor's securities' expected returns. The equation for the expected return of a portfolio with three securities is as follows:
Expected return = (weight of security A) x (expected return of security A) + (weight of security B) x (expected return of security B) + (weight of security C) x (expected return of security C)
To calculate the expected return of an investor's portfolio, the investor needs to know the expected return of each of the securities in his portfolio as well as the overall weight of each security in the portfolio.
An investor bases the estimates of the expected return of a security on the assumption that what has been proven true in the past will continue to be proven true in the future. The investor does not use a structural view on the market to calculate the expected return. He finds the weight of each security in the portfolio by taking the value of each of the securities and dividing it by the total value of the security.
Once the expected return of each security is known and the weight of each security has been calculated, an investor simply multiplies the expected return of each security by the weight of the same security, and adds up the product of each security.
Since the market is volatile and unpredictable, calculating the expected return of a security is more guesswork than definite, and it could cause inaccuracy in the calculated expected return of a portfolio.

How do I calculate my yeartodate (YTD) return on my portfolio?
Calculating the yeartodate return of a portfolio, including examples of yeartodate return calculations, with and without ... Read Answer >> 
Does working capital include marketable securities?
Learn how marketable securities such as Treasury bills (Tbills) and commercial papers are part of current assets and the ... Read Answer >> 
Determining expected market return with market risk premium
Find out how the expected market return rate is determined when calculating market risk premium – and how to estimate investment ... Read Answer >> 
What is a good annual return for a mutual fund?
Learn the key factors that determine if a mutual fund's return is "good" for you and your needs? Read Answer >> 
What is the difference between expected return and variance?
Learn about expected return and variance, the difference between the two measures and how to calculate the expected return ... Read Answer >>

Investing
Explaining Expected Return
The expected return is a tool used to determine whether or not an investment has a positive or negative average net outcome. 
Financial Advisor
Example of Applying Modern Portfolio Theory (MPS)
Modern Portfolio Theory: brush up on key mathematical framework used in investment portfolio construction. 
Investing
How to Calculate Required Rate of Return
The required rate of return is used by investors and corporations to evaluate investments. Find out how to calculate it. 
Retirement
The 3 Best Social Security Calculators For 2016
Find out how to analyze your Social Security benefits under different retirement scenarios using multifunctional online Social Security calculators. 
Investing
How to Calculate Your Investment Return
How much are your investments actually returning? Find out why the method of calculation matters. 
Investing
How To Profit From Investment "Losers"
Diversification and rebalancing are keys to longterm returns. 
Investing
Analyzing Mutual Fund Risk
Find out whether a fund's performance is a result of the manager's abilities, or just a fluke. 
Investing
Introduction To Fundamentally Weighted Index Investing
If you believe the market smiles on those who focus on value, growth or income, this vehicle may be for you. 
Managing Wealth
Achieve Optimal Asset Allocation
Minimize risk while maximizing return with the right mix of securities and achieve your optimal asset allocation. 
Investing
Strategies For Determining The Market's True Worth
Learn the strengths and weaknesses of passive and active management when trying to uncover the overall market's worth.

Overweight
1. A situation where a portfolio holds an excess amount of a ... 
Market Portfolio
A theoretical bundle of investments that includes every type ... 
Portfolio Return
The monetary return experienced by a holder of a portfolio. Portfolio ... 
Mean Return
1. In securities analysis, it is the expected value, or mean, ... 
Weighted
Weighted is a description of adjustments to a figure to account ... 
Relative Return
Relative return is the return an asset achieves over a period ...