Shall vs should: How to decide 

For English learners, it can be difficult to decide when to use shall vs should. The word shall is used to show certainty of intention about an action that will happen in the future. The word should is used to express uncertainty and to give suggestions or advice. Shall is used more in formal writing, like legal documents. Should is used in common conversation and writing.

Let’s get some advice on the difference between shall and should and why it’s important.  

• Difference between shall and should
• Examples of should vs. shall
• Why you need to know the difference between shall and should

Differences between shall and should

Before deciding to use shall or should let’s review what type of words shall and should are, grammatically speaking. 

Shall and should are modal verbs. Modal verbs are a type of auxiliary or helping verb. They work with other verbs to express different meanings such as conditionality, necessity, obligation, ability and wishful desire.  

The modal is always followed by a verb in the infinitive form.

A modal verb works with another verb to weaken or strengthen the verb and to add clarity to what you are saying. 

Shall expresses certainty

The word shall is used to express something that will happen. Shall expresses certainty. Shall is also used for ideas related to rules or laws. 

When you practice English grammar exercises, you will notice another modal word: must. Must is another modal used to demonstrate obligation. You will see it when talking about rules, but don’t confuse it with shall. 

• I shall go to the supermarket. 
• We shall be arriving around noon today. 
• Airline passengers shall listen to the flight attendants. 

Should expresses duty

Should is used to express obligation or duty, to express a personal opinion or to give advice. We like to tell people what they should do. 

• You should exercise. 
• They should be quiet at the library.
• I should read more books. 

Examples of should vs. shall

Let’s look at some examples of when to use each.

Tip: “Shall” is interchangeable with the word “will”. They both express certainty about the future.  If you aren’t sure about using should vs. shall, try replacing it with the word “will”. If it fits, “shall” is the right choice. 

Why you need to know the difference between shall and should

Using shall and should interchangeably can create confusion. We use these words for advanced business vocabulary and official documentation.

Here are some examples you could see in a legal document:

• The renter shall pay the landlord on the first of every month. 
• If there are objections to the agreement the individuals shall inform the judge. 
• The renter shall be reimbursed for any expenses over $80.

When you see the word shall in a legal document it means something must happen. If you have signed the document, your actions are legally binding. If you understand the word to mean something else, then you could have serious problems! 

Shall vs should, now you know!

You should study English every day. I shall quiz you later on what you learned. Remember, should expresses uncertainty or opinions and shall expresses certainty and rules. You should know the difference. And you shall use the words correctly from today forward.

Alison Maciejewski Cortez is Chilean-American, born and raised in California. She studied abroad in Spain, has lived in multiple countries, and now calls Mexico home. She believes that learning how to order a beer in a new language reveals a lot about local culture. Alison speaks English, Spanish, and Thai fluently and studies Czech and Turkish. Her consulting business takes her around the world and she is excited to share language tips as part of the Lingoda team. Follow her culinary and cultural experiences on Twitter.