2 Digit Addition
2 digit addition is a form of addition that contains just 2 digits arranged in their respective place values. One digit addition can be calculated mentally whereas 2 digit addition can be done mentally as well as following certain basic steps. 2 digit addition is one of the easiest forms of additions. Let us learn the basic steps of adding 2 digit numbers together.
1.  What is 2 Digit Addition? 
2.  2 Digit Addition With Regrouping 
3.  2 Digit Addition Without Regrouping 
4.  2 Digit Addition of Decimals 
5.  FAQs on 2 Digit Addition 
What is 2 Digit Addition?
2 digit addition is done by keeping in mind the place value of numbers. Numbers with 2 digits have the place value as ones and tens. While adding 2 digits together, we arrange the numbers in a columnwise manner under the respective place value. This method helps in adding the digits one by one. 2 digit addition is done in two methods, one is with regrouping (carrying forward) and without regrouping (no carrying forward). The numbers that are being added are called addends and the answer that is obtained after adding these numbers is called their sum.
2 Digit Addition With Regrouping
2 digit addition with regrouping is a method used when the sum of the numbers in one column is more than 9, we carry forward the number to the next column. In the case of 2 digit numbers, regrouping or carrying forward occurs from the ones column to the tens column. The basic steps to follow while adding 2 digits with regrouping are:
 Step 1: Arrange the numbers or addends according to their place value i.e. ones and tens in a columnwise or vertical manner.
 Step 2: Start adding the numbers from the right i.e. the ones column and proceed towards the left i.e. tens column.
 Step 3: If the sum in the ones column is more than 9, we obtain a doubledigit number again. From the doubledigit number, we place the number of the ones column under the ones column and the tens number is carry forward or regrouped to the tens column of the original numbers.
 Step 4: While adding the tens column, we include the tens number that was carried forward from the ones column.
 Step 5: Once both the columns are added, we obtain the final sum.
Let us look at an example to understand the steps better. Add 59 and 23.
As we can see in the above image, we have obtained the sum by adding 59 and 23 by regrouping method. Here is the look at it stepwise:
 Step 1: Arrange 59 and 23 according to their place value. 9 and 3 in the ones column and 5 and 2 in the tens column.
 Step 2 + 3: Add 9 + 3 = 12. Since 12 is greater than 9, we carry forward 1 to the tens column and write 2 as the sum in the ones column.
 Step 4: Include the 1 that was carried forward from ones column. Hence we add 5 + 2 + 1 = 8.
 Step 5: Both the columns are added. Therefore, 59 + 23 = 82.
2 Digit Addition Without Regrouping
2 digit addition without regrouping is the simplest form of addition. This method is used in daily life while shopping or doing any financial transaction. Here, when the sum is less than or equal to 9, we write the number under the respective place value column and do not carry forward any number to the next column. 2 digit addition without regrouping uses similar steps as regrouping but with subtraction of few steps. Let us see the basic steps used while adding 2 digit numbers without regrouping:
 Step 1: Arrange the numbers or addends according to their place value i.e. ones and tens in a columnwise or vertical manner.
 Step 2: Start adding the numbers from right to left i.e. one to tens.
 Step 3: Once both the columns are added, we obtain the final sum.
Let us look at an example to understand the steps better. Add 45 and 31.
As we can see in the above image, we have obtained the sum by adding 45 and 31 by using the without regrouping method. Here is the look at it stepwise:
 Step 1: Arrange 45 and 31 according to their place value. 5 and 1 in the ones column and 4 and 3 in the tens column.
 Step 2: Start adding the ones columns, 5 + 1 = 6. Move on to the tens column, 4 + 3 = 7.
 Step 3: Both the columns are added. Therefore, 45 + 31 = 76.
2 Digit Addition of Decimals
2 digit addition of decimals is done in a similar manner as done for regrouping and without regrouping. In decimals, numbers are written according to their place value and decimal point. Addition is done normally from right to left and if the sum is more than 9, we carry forward to the next column. The steps are the same as mentioned before. Let us look at an example for both regrouping and without regrouping.
2 Digit Addition of Decimals With Regrouping
For decimals, we use the same steps as used before for regrouping. Let us look at an example, add 3.9 and 1.2.
As we can see in the above image, we have obtained the sum by adding 3.9 and 1.2 by regrouping method. Here is the look at it stepwise:
 Step 1: Arrange 3.9 and 1.2 according to their place value i.e. ones and tenths. 9 and 2 in the tenths column and 3 and 1 in the ones columns.
 Step 2: Start adding from the right. so 9 + 2 = 11. Here, we carry forward 1 to the ones column and write 1 in the tenths column.
 Step 3: Add the numbers in the ones column along with the carried forward number. 3 + 1 + 1 = 5.
 Step 4: Once both the column numbers are added we obtain the final sum. Therefore, 3.9 + 1.2 = 5.1.
2 Digit Addition of Decimals Without Regrouping
For decimals without regrouping, we use the same steps as used for without regrouping 2 digit numbers. Let us look at an example, add 6.2 and 3.2.
As we can see in the above image, we have obtained the sum by adding 6.2 and 3.2 by using without regrouping method. Here is the look at it stepwise:
 Step 1: Arrange 6.2 and 3.2 according to their place value i.e. ones and tenths. 2 and 2 in the tenths column and 6 and 3 in the ones columns.
 Step 2: Start adding from the right. so 2 + 2 = 4. Move on to the next column, 6 + 3 = 9.
 Step 3: Once both the columns are added we obtain the final sum. Therefore, 6.2 + 3.2 = 9.4.
Note: While adding 2 digit numbers, the decimal point does not move and remains in the same position.
Related Topics
Listed below are a few interesting topics related to 2 digit addition, take a look.
Examples on 2 Digit Addition

Example 1: Add the 2 digit numbers 87 and 13.
Solution:
Let us write the numbers in a columnwise or vertical manner. Start adding the numbers in the ones column and move ahead to the tens column.
Numbers in the ones column: 7 + 3 = 10. (we carry forward 1 to the tens column)
Numbers in the tens column: 8 + 1 + 1 = 10. (since we do not have another column, we write the number as it is)
Therefore, 87 + 13 = 100.

Example 2: Add the 2 digit numbers 51 and 47.
Solution:
Let us write the numbers in a columnwise or vertical manner. Start adding the numbers in the ones column and move ahead to the tens column.
Numbers in the ones column: 1 + 7 = 8.
Numbers in the tens column: 5 + 4 = 9.
Therefore, 51 + 47 = 98.

Example 3: Add the 2 digit numbers with decimal points, 4.1 and 2.5.
Solution:
Let us write the numbers in a columnwise or vertical manner. Start adding the numbers in the ones column and move ahead to the tens column.
Numbers in the ones column: 1 + 5 = 6.
Numbers in the tens column: 4 + 2 = 6.
Therefore, 4.1 + 2.5 = 6.6.
FAQs on 2 Digit Addition
What is Addition of TwoDigit Numbers?
Addition of twodigit numbers is a simple form of addition that is done similarly to onedigit addition. Here, numbers are arranged according to their place value. In 2 digit addition, the place value is ones and tens. Arrange the numbers according to the place value vertically and start adding from right to left which is ones column to tens column. Once both the columns are added, we obtain the final sum. Addition of twodigit numbers is done in two methods  regrouping and without regrouping.
How Do You Do 2 Digit Addition Without Regrouping?
2 digit addition without regrouping is done in a simple and straightforward manner. Here are the steps:
 Arrange the numbers vertically or columnwise according to their place value.
 Start adding from right to left i.e. ones column first then tens column.
 Once the sum is obtained for both columns, we arrive at the final number.
For example: 16 + 10 = 26.
How Do You Teach Carrying 2 Digit Addition?
Carrying is the other name for regrouping. 2 digit addition with regrouping is done when the sum of the first column (ones column) is more than 9, we carry forward the number to the tens column (corresponding column). The steps to teach carrying 2 digit addition is:
 Arrange the numbers vertically according to the place value.
 Start adding the numbers in the ones column. If the sum is more than 9, we carry forward the tens numbers to the tens column and write the number in the ones place under the ones column.
 Start adding the tens column by including the number that was carried forward from the ones column.
 Once the sum is obtained for both columns, we arrive at the final sum.
For example: 29 + 41 = 70. (Numbers in the ones column = 9 + 1= 10. Carry forward the number 1 to tens columns. Numbers in the tens column = 2 + 4 + 1 = 7).
How Do You Do 2 Digit Addition of Decimals?
2 digit addition of decimals is performed in the same manner as 2 digit addition with regrouping and without regrouping. The decimal point does not move away from the numbers and the addition is done normally. Once the numbers are arranged vertically, the addition is performed normally. For example: 7.5 + 2.4 = 9.9.
How Do You Add ThreeDigit Double Digits?
Adding a threedigit doubledigit is done in a similar manner as adding 2 digit numbers. The numbers are written according to their place values i.e. ones and tens. To add the two digits, we begin from the right to left until both the place values have been added. The numbers are arranged vertically or columnwise for simple addition.
How Do You Add 2 Digit Numbers Mentally?
To add 2 digit numbers mentally, we need to add numbers separately. First, we add numbers in the ones column and then move on to the tens column. The steps to addition are the same as normal addition but here we do it in our minds. While carrying forward or regrouping, we keep that number in the mind and then add.
visual curriculum