Determining the expired domain name's type

The first step in buying an expired domain name is determining which of the 6 types it falls under (pre-release, closeout, on hold, redemption period, dropping, and deleted). If you already know its type, skip directly to the corresponding section below.

If you don't know its type, check its expiry date in WHOIS. If the expiry date is 1-30 days in the past, contact the domain name's registrar to find out how to acquire it. The registrar is usually listed in the WHOIS results as the "Registrar", "Sponsoring Registrar", or "ICANN Registrar".

If the expiry date is 31 or more days in the past, check its Registrar Status in the WHOIS results. If it says pendingdelete, it's considered a dropping domain name.

Once you've obtained its type, you can begin the process of acquiring it. Listed below are the 6 types of expired domain names, along with buying specifics.
Pre-Release Domain Names

A pre-release domain name is one that has not been renewed by the original owner before its expiry date, and is being sold by its registrar in an open auction to the highest bidder. The term "pre-release" is used because the domain name is being made available for sale before it is released to the registry, where it would eventually drop and become available to anyone through a backorder.

How to Buy: A pre-release domain name can only be acquired from its auction source. To identify its auction source, contact the domain name's registrar.

A few of the more popular pre-release auction sources are:

    SnapNames
    TDNAM
    NameJet

Closeout Domain Names

A closeout domain name, also known as a "firesale domain name", is one that has not been renewed by the original owner before its expiry date, has not been bought in a pre-release auction, and is being sold by its registrar at a discounted BIN (Buy it Now) price. The term "closeout" is used because it is the last chance to buy the domain name from the registrar before they release it to the registry, where it would eventually drop and become available to anyone through a backorder.

How to Buy: A closeout domain name can only be acquired from its BIN source. TDNAM is the only source currently selling closeout domain names, selling them on a first-come, first-served basis.
On Hold Domain Names

An on hold domain name is one that has not been renewed by the original owner before its expiry date, and has been placed under the REGISTRAR HOLD or REGISTRY HOLD statuses. Although the majority of domain names under these statuses are legitimate expired domain names, there may be some that are the subject of a legal dispute.

How to Buy: An on hold domain name can only be acquired by contacting the owner, having them renew the domain name's registration, and then buying it directly from them.
Redemption Period Domain Names

A redemption period domain name is one that has not been renewed by the original owner before its expiry date, and has been placed under the REDEMPTION GRACE PERIOD or REDEMPTIONPERIOD statuses.

How to Buy: A redemption period domain name can only be acquired by contacting the owner, having them renew the domain name's registration, and then buying it directly from them.
Dropping Domain Names

A dropping domain name is one that has not been renewed by the original owner before its expiry date, and is scheduled for deletion from the registry. The term "dropping" is used because the domain name is being dropped (deleted) from the registry.

How to Buy: A dropping domain name can be acquired by anyone the moment it is dropped from the registry. Because of the competition for many dropped domain names, the most effective method of acquiring one is through a backorder service (also know as a drop catching service).

A few of the more popular backorder services are:

    GoDaddy
    NameJet
    Pool
    SnapNames

Deleted Domain Names

A deleted domain name, in the context of expired domain names, is one that has been deleted (dropped) from the registry. The term "deleted" is used as it references an expired domain name that has already been deleted/dropped.

How to Buy: So long as it has not been registered by someone else first, a deleted domain name can be acquired in the exact same way as a regular unregistered domain name.

Let me know how it goes in the comments below.