Short answer

• Your broker will issue a margin call and may require you to deposit cash or marginable securities to bring the account back up to the required maintenance level. If you don’t meet the call, the broker can liquidate (sell) some or all of your positions without your permission to restore the required equity. You may also owe money if sales don’t cover the deficit.

What it means (brief)

• Maintenance margin is the minimum equity percentage your broker requires in a margin account after you’ve borrowed to buy securities.
• If your account equity (market value of securities − loan balance) falls below that minimum, the account is under-maintained and the broker will act.

Typical broker actions

• Margin call: broker notifies you to deposit funds or acceptable securities. Some brokers give a short time window; others require immediate action.
• Forced liquidation: if you don’t meet the margin call, the broker may sell positions (partially or fully) without prior approval to restore required equity.
• Restrictions: the broker may restrict new purchases, convert marginable positions to cash margin, or limit transfers.
• Fees and interest: you’ll continue to be charged interest on the borrowed amount; additional fees or administrative costs may apply.
• You may still owe money: if market moves are large and sales don’t cover the loan plus fees, you’re responsible for the negative balance.

Important details to know

• Maintenance requirement varies: different brokers and different securities have different maintenance rates (commonly 25%–40% for stocks; higher for volatile or concentrated positions). Check your broker’s schedule.
• Calculation: Equity = Market value of securities − Debit (loan) balance. Maintenance margin requirement = Maintenance rate × Market value. Under-maintained if: Equity < Maintenance margin requirement.
• Example: You own Rs. 200,000 of stock with a Rs. 100,000 loan (equity = 100,000). If maintenance rate is 30% then required equity = 30% × 200,000 = 60,000. You are OK (100,000 > 60,000). If the stock falls to Rs. 150,000, equity = 150,000 − 100,000 = 50,000, which is below required 45,000? (calculate correctly:) Required = 30%×150,000 = 45,000 — in this case you still meet it. If it fell to Rs. 140,000, equity = 40,000 and required = 42,000 → margin call.

Ways to respond to a margin call

• Deposit cash.
• Transfer or deposit eligible marginable securities.
• Sell some holdings (you can sell positions yourself before broker liquidates).
• Reduce exposure by closing positions.

Risks & best practices

• Rapid market moves and after-hours/gap risk can leave you vulnerable to immediate liquidation and a negative balance.
• Brokers can liquidate any collateral without contacting you in many jurisdictions and are not required to sell the least-loss position.
• Keep a buffer above maintenance (target higher equity, e.g., 5–10% more than required).
• Know your broker’s specific margin rules, notification method, timelines, and fees.
• Consider limiting leverage, using stop-losses carefully, or moving risky positions to cash accounts.

When to contact your broker

• Immediately if you see your equity approaching the maintenance requirement or if you receive a margin call. Ask for the exact amount required, any deadlines, and whether partial deposits will be accepted.

If you want, I can:

• Walk through a numeric example with your specific numbers (current market value, loan balance, and your broker’s maintenance rate), or
• Summarize typical maintenance rates and margin rules for common Indian brokers (I’d need to check current broker terms first).