What it means
If you look at the bottom of a cheque, you will see strange blocky digits. Those are printed in ink containing magnetic particles, and a reader can detect them even if the cheque has been stamped, scribbled on or smudged.
The shapes of the characters are standardised so machines can tell them apart. The line usually contains three pieces of information: the bank or routing number, which identifies the institution where the account is held, the account number and the cheque number.
Symbols between the numbers act as separators. In the United States, the routing number has nine digits, and the last digit is a check digit that lets a machine spot errors.
The formula multiplies the digits by repeating weights of 3, 7 and 1 and requires the total to be a multiple of 10. This allows a bank to detect many typing errors before a payment is sent.
Different countries use different standards, with two main typefaces in use around the world. Layouts and number lengths also vary by country, so a cheque from one country may not be processed in the same way as another.
Cheques are now less common, and many are cleared by scanning an image, but the MICR line remains an important part of the process. For a business, getting the MICR line right matters.
A badly printed line, wrong ink or an altered account number can cause a cheque to be rejected, delayed or even used fraudulently. Companies that print their own cheques need approved stock and printers, and should protect their blank cheques carefully.
Never share a full MICR line casually, because the account and routing numbers it shows are enough to attempt a payment. Treat images of cheques with the same care as the paper originals.
In practice
Real-world examples.
Example
A payroll clerk orders a new set of cheque stock for the company. The printer encodes the MICR line with the account and routing numbers, and the clerk checks a sample against the bank's confirmation before issuing any payments.
Example
A bank's cheque processing centre runs thousands of cheques through a reader every hour. The machine reads the MICR line, sorts each cheque by the paying bank and posts the amount to the right account.
Example
A small business owner receives a cheque with a faded line. The bank asks her to deposit it again with a cleaner copy, because the reader cannot capture the account details, and the delay holds up $4,500 of cash.
Formula
Calculation
Check sum = 3 x (d1 + d4 + d7) + 7 x (d2 + d5 + d8) + 1 x (d3 + d6 + d9), and the total must be divisible by 10
Take the nine-digit number 123456780, used here as an invented example and not a real bank. The digits in positions 1, 4 and 7 are 1, 4 and 7, which add to 12, and 3 x 12 = 36. The digits in positions 2, 5 and 8 are 2, 5 and 8, which add to 15, and 7 x 15 = 105. The digits in positions 3, 6 and 9 are 3, 6 and 0, which add to 9, and 1 x 9 = 9. The total is 36 + 105 + 9 = 150, which is divisible by 10, so the number passes the check.Case study
Seen in the real world.
Beacon Hardware is an illustrative, fictional chain that receives about 2,000 cheques a month from trade customers. The finance manager found that around 4% were being rejected or delayed because of poorly printed MICR lines on customers' cheques, which held up roughly $60,000 of cash each month.
She set up a process in which staff checked the line at deposit and contacted customers whose cheques were unclear. She also encouraged the biggest customers to move to electronic transfers. After six months, the rejection rate fell to 1%, and average collection time dropped by three days.
The fictional company also tightened controls on its own cheque stock by locking it away and logging each batch. The illustrative lesson was that a small detail on a cheque can have a measurable effect on cash flow and fraud risk.
Watch out
Common mistakes.
- Treating the MICR line as decorative, when machines rely on it to route and post the payment.
- Printing cheques on ordinary toner or ink, which can make the line unreadable by bank equipment.
- Leaving blank cheques unsecured, since the line contains the information needed to attempt a payment.
Questions
People also ask.
What information is in the line?
It normally carries the bank routing or sort code, the account number and the cheque number, separated by special symbols.
Why is magnetic ink used?
Readers can detect the magnetic signal even when the cheque is marked, folded or stamped, which makes machine reading reliable.
Are cheques still processed this way?
Many are now cleared using scanned images, but the MICR data is still read and used to identify the account and bank.
From the founder's library
Take it further with the book.
Build your financial confidence beyond this definition. Shihan's full-length guide, Accounting Fundamentals, takes the same plain-English approach and turns it into a complete, practical playbook for non-finance managers, business owners and students - with chapter-end quiz answers and presentation slides included.
25% off with code MMHQ25, applied at checkout. Priced in USD - checkout may show the equivalent in your local currency.
View the book and save 25%Related