How to Buy CBA Shares (and the Exposure You Already Have)

📋 What you need first🔗

Four things, and none of them are difficult.

• A brokerage account. You cannot buy ASX shares without one. Our broker comparison covers what actually differs between them.
• A linked bank account to fund it. Most brokers want the money in place before you can place a buy order.
• Your tax file number. You are not obliged to provide it, but without it tax is withheld from investment income at the top rate, so there is no upside to withholding it.
• Identification. Licensed brokers have to verify who you are under anti money laundering rules. A licence or passport is standard.

🪜 The six steps🔗

1. Choose a broker, and check whether it is CHESS sponsored or uses a custodian, because that decides whose name the shares are registered in. Our CHESS sponsorship guide explains what rides on the answer.
2. Open and verify the account, which is mostly digital and can take anywhere from minutes to a couple of business days depending on identity checks.
3. Search the ticker CBA, three letters, and confirm the name that comes up is Commonwealth Bank of Australia before going further.
4. Choose your order type. A market order buys at the next available price. A limit order sets your maximum and only fills if the market reaches it.
5. Review and confirm: ticker, number of units, order type, and the brokerage shown on screen.
6. Keep the contract note. It records what you paid including brokerage, which is your cost base when you eventually sell and calculate capital gains.

🎯 The essential: Enter the number of units, not a dollar amount. If the price is around $180 and you want to invest roughly $1,800, you are buying 10 units. Brokers that let you enter dollars are usually the fractional, custodian kind.

📄 Your holding statement🔗

A couple of business days after the trade, it settles and you get a holding statement. If your broker is CHESS sponsored, that statement carries your Holder Identification Number, which starts with X and belongs to you rather than to the broker.

That is the practical value of CHESS sponsorship: the shares are registered in your name, so a broker failing does not put them in question. The settlement timing is covered in what T+2 actually means.

💰 Dividends and franking🔗

A dividend is a share of profit paid out in cash, and Australian banks have historically been regular payers, though any dividend is at the company’s discretion and can be cut.

Four dates matter, in this order:

• Declaration: the company announces the dividend.
• Ex-dividend: the cut-off. Buy on or after this date and the seller keeps the payment.
• Record: the company checks who is on the register.
• Payment: the cash arrives, or new shares are issued if you have elected to reinvest.

Franking credits represent company tax already paid on those profits. You declare the cash and the credits, then claim the credits as an offset, so the same profit is not taxed twice. A minimum holding period applies before you can claim the offset, which matters if you are buying just before an ex-dividend date, so check the current ATO position rather than assuming. Our guide to the ex-dividend date sets out the sequence.

🔁 Reinvesting instead of taking cash🔗

A dividend reinvestment plan issues you new shares instead of paying cash. You elect into it through the company’s share registry rather than through your broker, and the registry details are on the company’s own investor relations pages.

Two things to know before you tick the box. Each reinvested parcel has its own cost base for capital gains purposes, so years of reinvesting means years of parcels to keep records for. And reinvesting automatically buys more of the same company, which compounds your position and your concentration at the same time.

⚠️ The exposure you already have🔗

This is the part worth slowing down for, because it is the bit that surprises people.

If you hold a broad Australian shares ETF, you already own this bank. Those funds weight by company size, and the big banks sit near the top. Buying the shares directly does not add a new holding, it doubles an existing one.

Then there is your super. Default options carry a meaningful allocation to Australian shares, and that allocation holds the same large companies for the same reason.

The broader point about owning one company versus many is covered in building a simple portfolio.

❓ Frequently asked questions🔗

🔗 Sources🔗

• How to buy and sell shares, Moneysmart, Australian Securities and Investments Commission, updated 18 June 2026.
• Start investing, Australian Securities Exchange.
• Imputation, Australian Taxation Office, on how franking credits work.
• Diversification, Moneysmart, Australian Securities and Investments Commission.