What Is 'MBS Pool Number'

The MBS pool number is an alphanumeric code that identifies a particular mortgage-backed security (MBS). The MBS pool number is one way to pinpoint a mortgage-backed security when looking for further information. MBS pool numbers are typically six digits in length and are assigned by the issuer according to internal naming conventions. Different issuers such as Freddie Mac, Fannie Mae and Ginnie Mae use different alpha characters as the initial digit in their MBS pool numbers to identify the pool as their issue. For example, a Freddie Mac 30-year pool number might be D54321 while a Fannie Mae 30-year pool number might be F54321. The MBS pool number is sometimes referred to as the MBS series number.

Breaking Down 'MBS Pool Number'

MBS pool numbers are simply a label that distinguishes one MBS from another. Issuers use specific naming conventions, so MBS traders learn to identify the issuer from the pool number. This is a critical skill for research, as you can then jump directly to the issuer's pool number lookup system to access disclosures related to that MBS.

MBS Pool Numbers Versus CUSIP Numbers

MBS traders favor pool numbers over CUSIP. The CUSIP and the MBS pool number get you to the same place, but the MBS pool number is part of a pseudo-ticker that includes an identifier of the issuer, the pool type, the issue date, the issuer ID and so on. To get that same information using the CUSIP, you have to go through the extra step of the lookup. When traders refer to the pool number, they are often speaking about the larger pool record that includes all the information, rather than the specific six-digit identifier. Regular issuers of mortgage-backed securities have set up naming conventions with suffixes and prefixes that show whether an MBS is a single family loan pool, construction loan pool and so on. Traders can get most of the information they are seeking from this expanded record without diving into disclosure forms. Even just working with the pool number, traders who regularly look at them will be able to distinguish between newer issues and older issues from the same issuer. 

Although the MBS pool number and its accompanying prefixes and suffixes can pass on a lot of information as to the type and character of the security, investors need to go to the lookup pages that are usually hosted on the issuers' websites to get into the details. These lookup pages will generally accept either the CUSIP number or the pool number. Once that is provided, investors can access historical information on coupons, detailed information on the stratification of the issue into tranches, loan level information on the borrowers, interest adjustment dates and much more. 

  1. Pool Factor

    The pool factor is a measure of how much of the original loan ...
  2. Agency MBS Purchase

    Agency MBS purchase is most commonly used to refer to the U.S. ...
  3. Whole Pool

    A whole pool is an undivided interest in a group of mortgages ...
  4. 48-Hour Rule

    The 48-hour rule requires that all pool information regarding ...
  5. Jumbo Pool

    A jumbo pool is a mortgage-backed security that is collateralized ...
  6. Option Pool

    An option pool is stock in a startup that is set aside to be ...
Related Articles
  1. Investing

    Profiting Off of Increased Mortgage Rates (PTRIX,FMSFX,VMBSX)

    Learn why mutual funds that invest in mortgage-backed securities (MBS) are worth a look for investors wanting to capitalize on rising mortgage interest rates.
  2. Investing

    Swimming Pools: Costs Vs. Long-Term Value

    Consider the costs of installing and maintaining a swimming pool, and compare this with the pool's utility and the market value it adds to your home.
  3. Investing

    Top 3 Mortgage Backed Securities (MBS) ETFs (MBB, MBG)

    Discover some of the best opportunities for investors seeking exposure to mortgage-backed securities through utilizing exchange-traded funds.
  4. Investing

    Asset-backed and mortgage-backed securities: An introduction

    Learn more about the structure of asset-and mortgage-backed securities, securities backed by pools of mortgage or non-mortgage assets, along with some examples of ABS, MBS and their valuations. ...
  5. Investing

    The Impact of Rising Mortgage Rates on ETFs

    Mortgage rates reached seven-year highs last month, and some fixed-income ETFs are feeling the effects.
  6. Personal Finance

    Profit From Mortgage Debt With MBS

    Mortgage-backed securities can offer monthly income, a fixed interest rate and even government backing.
  7. Insights

    An Introduction to Dark Pools

    Dark pools are an ominous-sounding term for private exchanges or forums for trading securities; unlike stock exchanges, dark pools are not accessible by the investing public.
  8. Investing

    Asset Allocation In A Bond Portfolio

    An investor's fixed-income portfolio can easily beat the average bond fund. Learn how and why!
  9. Insights

    The Mortgage-Backed Security Market Faces Major Tumoil

    The Fed is expected to begin selling off its $1.75 trillion portfolio of mortgage-backed securities.
  10. Insights

    Should You Be Afraid Of Dark Pool Liquidity?

    Don't fear the deep end. Dark pool liquidity can help drive down stock cost for everyday investors.
  1. Are all mortgage backed securities (MBS) also collateralized debt obligations (CDO)?

    Learn more about mortgage-backed securities, collateralized debt obligations and synthetic investments. Find out how these ... Read Answer >>
  2. Collateralized Mortgage Obligation vs. Collateralized Bond Obligation

    Determine how collateralized mortgage obligations (CMOs) and collateralized bond obligations (CBOs) differ in the types of ... Read Answer >>
  3. The Differences Between a Collateralized Debt Obligation (CDO) and an Asset Backed ...

    Learn about the differences in relationships between asset-backed securities (ABS) and collateralized debt obligations (CDOs) Read Answer >>
  4. Who Bears the Risk of Bad Debts in Securitization?

    Bad debts arise when borrowers default on loans. But that risk can be split up in different ways. Read Answer >>
Hot Definitions
  1. Current Assets

    Current assets is a balance sheet account that represents the value of all assets that can reasonably expected to be converted ...
  2. Volatility

    Volatility measures how much the price of a security, derivative, or index fluctuates.
  3. Money Market

    The money market is a segment of the financial market in which financial instruments with high liquidity and very short maturities ...
  4. Cost of Debt

    Cost of debt is the effective rate that a company pays on its current debt as part of its capital structure.
  5. Depreciation

    Depreciation is an accounting method of allocating the cost of a tangible asset over its useful life and is used to account ...
  6. Ratio Analysis

    A ratio analysis is a quantitative analysis of information contained in a company’s financial statements.
Trading Center