Micro-deposits are small sums of money that are transferred online, from one financial account to another. The deposits are typically less than $1 and are sent to your account by another financial institution to verify it is the correct account.

Micro-deposits might show up on your bank statement as a temporary credit of anywhere between $0.02 or $0.40. They are also usually deposited in pairs—so, your statement would show two micro-deposits to your account within one to three business days of linking your accounts.

Banks and other financial institutions use micro-deposits as a security measure. Specifically, they’re used to verify account ownership.

For example, if you’re attempting to link your bank account to another financial account (like an investment account), the new financial institution will want to make sure it has the right connection to another account. So, it will do a test run by initiating a micro-deposit.

A customer will be notified that a micro-deposit has been sent to his or her bank account, and will then receive a notification to verify the amount of the deposit by logging into the account. Once the customer has verified the amounts, the initiating party will withdraw the small deposits.

As micro deposits are used in IAV ( Instant Account Verification ), lets compare that in both Yodlee and Plaid

Yodlee provides two options:

Account validation and verification from Envestnet | Yodlee happens in real-time without requiring micro-deposits, routing numbers, or bank account numbers. Plus, account linking is intuitive, fast, and secure for a better user experience with Envestnet l Yodee FastLink.

Quickstart Guide: https://www.yodlee.com/account-verification

In the challenge deposit verification (CDV) process, Yodlee makes two micro deposits and a debit of amounts less than one dollar to the consumer's account by using the account number and routing number provided by him/her. Once the micro deposits and the debit are posted to the account, the consumer must check his/her statement or online transaction record to determine the exact amounts of the two deposits and the debit. The consumer must then return to the account verification application and input these amounts to confirm account ownership.

Docs: Matching and CDV | Yodlee Developer Portal

Plaid provides three options:

Instant Auth supports more than 3,800 financial institutions with credential-based login, which translates to roughly 90% coverage of all depository accounts in the US. Instant Auth is the default Auth flow and does not require extra configuration steps if Auth is already configured in your app. For clarity and completeness, the section below explains how to configure Instant Auth.

Instant Match is available for more than 2,500 financial institutions (US only) and is automatically provided at supported institutions as a fall-back experience when Instant Auth is not available. When using Instant Match, Plaid Link will prompt your user to enter their account number and routing number. Plaid will then verify the last four digits of the user-provided account number against the account mask retrieved from the financial institution.

The Automated Micro-deposits authentication flow is supported for ~3,200 financial institutions in the US only. Plaid will make a single micro-deposit and then automatically verify it within one to two business days.

Same Day Micro-deposits can be used to authenticate any bank account in the US, but especially for the ~2,000 institutions that don't support Instant Auth, Instant Match, or Automated Micro-deposit verification. Plaid will make two deposits that post within one business day (using Same Day ACH, which is roughly two days faster than the standard micro-deposit experience of two to three days). Users are instructed to manually verify the deposited amounts within one business day.

Final Thoughts:

Micro deposits verification can be achieved in Yodlee. For more, we need to look at this documentation: https://developer.yodlee.com/Matching_and_CDV

Releases: Yodlee API | Yodlee Developer Portal

Though, Yodlee's documentation of micro deposits is not as elaborative as account verification via fastlink.

Sandbox Bank Accounts for Micro deposits ( Auth flow )

Link: https://plaid.com/docs/auth/coverage/testing/