What Happens When You Buy a Stock? Behind the Buy Button

You tap Buy. Here is how one order for 10 shares can move from an instruction to a settled investment in your account.

Read the explanation

10 existing whole shares. €100 per share. A funded cash account on an EU exchange. Fees, FX and taxes excluded.

The successful €100 example

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The short version
  • A buy limit sets the highest price per share, but it does not guarantee a fill.
  • Filled confirms that the trade was executed, while the cash and shares still need to settle.
  • Because these shares already existed, the purchase money pays the selling side rather than raising new money for the company.
  • Custody arrangements vary. Some EU markets use indirect holding chains, while others also support investors holding directly.
The complete journey

One Tap, Several Market Layers

One tap sets several separate systems in motion. They execute the order, manage obligations, exchange cash and shares, and support the holding shown in your account.

Step 1

Your Order Starts as Instructions

You place a limit order for 10 shares at up to €100 each and choose how long it stays active. The app sends the order onward. Your cash does not accompany it to the exchange.

A buy limit sets the highest price per share, but it does not guarantee a fill.

The broker receives the share, quantity, price limit and order validity. The order may fill completely, fill partly or remain unfilled. Even if a displayed or recent price reaches €100, there may be too few shares available or other orders may have priority.

Step 2

The Broker Checks and Routes It

The broker checks the order and available funds, then routes it under its execution policy. In this example, the order reaches an EU exchange where prices and available orders are displayed.

The broker weighs price and costs alongside speed, order size, and the chances of execution and settlement.

The broker's policy sets which venues it may use, and another firm may execute the trade on its behalf. Routes differ between brokers and orders, so your order does not necessarily go to the exchange where the share is listed for trading.

Step 3

The Exchange Matches Buy and Sell Orders

The exchange's order book matches your buy order with eligible sell orders. In this illustration, it matches 10 available shares at €100 each, filling your order in full.

Filled confirms that the trade was executed, while the cash and shares still need to settle.

The exchange reports the executed quantity and price, and your broker sends you execution information or a confirmation. A different order could fill only partly or not at all, depending on available sell orders and its place in the queue.

Step 4

A Central Counterparty (CCP) Steps In

As this trade is registered for central clearing, a central counterparty stands between the buying and selling sides. Clearing members help manage the risk that either side fails to meet its obligations.

Netting can reduce how many separate share deliveries and cash payments market participants must make.

The central counterparty deals with clearing members rather than you directly. Its role can begin as the trade is registered, while trade reports and other processes continue. The exact arrangement varies, and some EU trades do not use a central counterparty.

Step 5

Cash and Shares Are Exchanged

Settlement links delivery of the 10 shares to the corresponding €1,000 payment. Securities move toward the buying side as cash moves toward the selling side through the accounts of market intermediaries.

Because these shares already existed, the purchase money pays the selling side rather than raising new money for the company.

Brokers may rely on clearing members, custodians and settlement banks to complete the exchange. Delivery versus payment links the two transfers, so neither side gives up its asset without receiving the other. Netting also means your exact euros need not reach one identifiable seller.

Step 6

What Supports the Holding You See

Your app may show the filled position before settlement completes. Once settled, broker and custodian records, together with the relevant securities holding chain, support the 10-share holding shown in your account.

Custody arrangements vary. Some EU markets use indirect holding chains, while others also support investors holding directly.

Under indirect holding, your custodian identifies you while intermediaries keep accounts further up the chain. Your name does not necessarily appear at the central securities depository or on the company's shareholder register. Seeing a filled position in the app alone does not prove settlement is complete.

Scope and sources

The example and its limits

This example follows a successful funded cash-account limit order for 10 existing whole shares priced at €100 each on an EU exchange with a visible order book: €1,000 before fees, foreign exchange costs and taxes. It excludes margin, derivatives, fractional shares, new issues, off-exchange execution and securities lending.

The Match step lets you compare a €99 and a €100 buy limit. Ten shares are offered at €100 when the order arrives. At €99 the order waits and the later steps remain unavailable. At €100 this example fills all ten shares. Real orders can also fill partly or remain unfilled as liquidity and queue priority change.

Cash and share figures illustrate this one trade, before fees and taxes. Broker cash reservations and account posting times vary. Market transfers can be netted. The custody scene shows one indirect holding arrangement; structures vary by market and broker.

About the author
Kai Schukowski · Founder, EU Investing Hub

Kai is an investor who helps people choose the right broker and invest with confidence. He founded EU Investing Hub, his European-focused investing site, and MatchMyBroker, a broker-comparison site for a global audience. He also runs the Smart Money with Kai YouTube channel, where he breaks down investing, brokers and personal finance.

Capital at risk. Provider of the investment services is Lightyear Europe AS for the EU. Terms apply: https://lightyear.com/terms. Seek qualified advice if necessary. This is not investment advice. Sponsored Link.
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