What are short selling borrowing costs and available shares?
There are conditions and costs for borrowing stocks. Do not extrapolate numbers from one screen to the entire market.
Table of contents
Remember this first
First, 3 things to remember
- 1Stock lending refers to the transaction of borrowing and lending shares.
- 2Short selling profit and loss include not only the price difference but also borrowing costs.
- 3The quantity available to borrow and the costs may vary depending on the provider and the timing.
Costs may accrue while borrowing
Securities lending is the act of borrowing and lending stocks. Numbers labeled as borrow fee or CTB are used for borrowing costs. You must check the explanation for the period and conditions of the costs.
If the term annual rate is used, it is a ratio based on 1 year. An annual rate of 10% does not mean you pay 10% today. Actual calculations depend on the brokerage firm's standards for days and amounts, as well as fluctuating rates.
Even if it is 0 shares in one place, it is not 0 shares for the entire market
A brokerage's lendable volume screen shows the quantity confirmed by that provider. Do not conclude that you cannot borrow more anywhere just because the number changes or becomes 0.
High costs do not necessarily mean the stock price will surge. Read information regarding borrowing conditions and future stock price trends separately.
There are obligations beyond price differences
Margin is a requirement, such as funds that must be maintained in an account to ensure transaction obligations can be met. If losses increase, additional funds may be required, or the brokerage may forcibly close the position.
You must also check the obligations related to dividend payments and the return conditions of the loan agreement. First, remember that this is not a transaction that ends without costs just by guessing the stock price correctly.
You should not make such assumptions
“If there are 0 shares available to lend, does that mean a short squeeze will definitely happen tomorrow?”
It may be the provider's volume at a specific point in time. It is not a number that determines the overall market situation or the next stock price.
Check what you have read.
- Which provider is the data from?
- Did you check if the cost is on a daily or annual basis?
- Have you checked costs other than the price difference and account conditions?
Apply what you read to the actual screen
Try it on WAPE
Source and scope of verification
Reviewed · Version 1
- An Introduction to Short SalesNew window
SEC · Investor.gov · Verify 2026-10-20
Structure of stock lending, short selling, and buybacks. · Potential for costs/losses and the legality of short selling - Margin AccountsNew window
FINRA · Verify 2026-10-20
Maintenance margin requirements and potential liquidation upon shortfall - Short Securities AvailabilityNew window
Interactive Brokers · Verify 2026-10-20
Available lending quantities and reference lending costs per brokerage are subject to change.
This is educational material for observation and information comprehension. Hypothetical examples do not represent actual stocks or performance and do not provide buy or sell recommendations.