What is Will?
Shall and will are both auxiliary verbs, also known as helping verbs. They are used together with other verbs to express specific meanings.
Technically speaking, will is used to express determination, inclination, or capability as in We will pay the money we promised or Caterpillars will turn into butterflies.
What is Shall?
Shall is used to express intent or determination as in I shall go to the store or She shall become the next queen.
Difference Between Will and Shall
The differences are subtle, but what is important to note is that both will and shall are used with all verbs to form the future tense.
The traditional rule of future tense says that shall is used in the first person (I shall eat lunch) and will is used in all other persons (you will eat lunch, she will eat lunch).
In practice, most English speakers do not follow this rule and the two words are considered to be interchangeable when forming the future tense. That being said, will is much more used for this purpose and shall is only used to sound more formal or old-fashioned.
Like many auxiliary verbs, will and shall may appear alone in sentences. In this case, the main verb is omitted but still understood. For example:
I don’t think you’ll do as well as you think you will (do).
We said that we’d clean the attic and we shall (clean it).
Both will and shall can be used to ask questions. Depending on the questions, will and shall may be used interchangeably or have distinct meanings.
For example, the questions What shall happen if we add water? And What will happen if we add water? Are asking the same thing: what event is going to occur when water is added. However, the questions Shall we arrive at noon? And Will we arrive at noon? Are asking different things: the first is asking if noon is an acceptable time to arrive while the second is asking whether or not we will arrive at noon.
In legal contracts, both will and shall are used to note that someone has a legal obligation or duty to do something. The specific rules and conventions regarding these words in legal contexts are ambiguous or vary from lawyer to lawyer.
In the Plain Writing Act of 2010, the US government recommends the use of the word must in place of shall to refer to a legal obligation.
Comparison Between Will and Shall
| Parameter of Comparison | Will | Shall |
| Overview | It is a modal verb. It can also be used as a noun in some cases. | It is a modal verb |
| Meaning | As a modal verb: To refer to the future (especially if it is planned or certain to happen) Willing/Able To request Order As a noun: Determination (will power) Document | As a modal verb: To suggest To refer to the future |
| Examples | Will you give me his address? This stew will feed ten people. He had a very strong will. | Shall we go out for lunch today? I shall never forget your voice. |