Mortgages may be legal or equitable. Furthermore, a mortgage may take one of a number of different legal structures, the availability of which will depend on the jurisdiction under which the mortgage is made. Common law jurisdictions have evolved two main forms of mortgage: the mortgage by demise and the mortgage by legal charge.


Mortgage by demise
In a mortgage by demise, the mortgagee (the lender) becomes the owner of the mortgaged property until the loan is repaid or other mortgage obligation fulfilled in full, a process known as "redemption". This kind of mortgage takes the form of a conveyance of the property to the creditor, with a condition that the property will be returned on redemption.

Mortgages by demise were the original form of mortgage, and continue to be used in many jurisdictions, and in a small minority of states in the United States. Many other common law jurisdictions have either abolished or minimised the use of the mortgage by demise. For example, in England and Wales this type of mortgage is no longer available, by virtue of the Land Registration Act 2002.


Mortgage by legal charge
In a mortgage by legal charge or technically "a charge by deed expressed to be by way of legal mortgage", the debtor remains the legal owner of the property, but the creditor gains sufficient rights over it to enable them to enforce their security, such as a right to take possession of the property or sell it.

To protect the lender, a mortgage by legal charge is usually recorded in a public register. Since mortgage debt is often the largest debt owed by the debtor, banks and other mortgage lenders run title searches of the real property to make certain that there are no mortgages already registered on the debtor's property which might have higher priority. Tax liens, in some cases, will come ahead of mortgages. For this reason, if a borrower has delinquent property taxes, the bank will often pay them to prevent the lienholder from foreclosing and wiping out the mortgage.

This type of mortgage is most common in the United States and, since the Law of Property Act 1925, it has been the usual form of mortgage in England and Wales (it is now the only form – see above).

In Scotland, the mortgage by legal charge is also known as Standard Security.

In Pakistan, the mortgage by legal charge is most common way used by banks to secure the financing.[citation needed] It is also known as registered mortgage. After registration of legal charge, the bank's lien is recorded in the land register stating that the property is under mortgage and cannot be sold without obtaining an NOC (No Objection Certificate) from the bank.


Equitable mortgage

Equitable mortgages don't fit the criteria for a legal mortgage, but are considered mortgages under equity (in the interests of justice) because money was lent and security was promised. This could arise because of procedural or paperwork issues. Based on this definition, there are numerous situations which could lead to an equitable mortgage. As of 1961, English law required the consent of the court before the equitable mortgagee was allowed to sell. When the borrower deposits a title deed with the lender, it has historically created an equitable mortgage in England, but the creation of an equitable mortgage by such a process has been less certain in the United States.

In an equitable mortgage the lender is secured by taking possession of all the original title documents of the property and by borrower's signing a Memorandum of Deposit of Title Deed (MODTD). This document is an undertaking by the borrower that he/she has deposited the title documents with the bank with his own wish and will, in order to secure the financing obtained from the bank.