When you execute a trade through your broker, you may not realise that it rarely happens directly on London Stock Exchange order books.
Instead, brokers have traditionally had to request prices from specialist market makers, known as Retail Service Providers (RSPs). These intermediaries offered prices in retail-size (relatively small) volumes and you could only trade at the price they provided.
However, more and more brokers are now offering a service called Direct Market Access (DMA), which allows you to place your orders directly on our order books in the same way that institutional investors do.
Useful links
Key advantages
Every order is of equal status on the order book, prioritised only in terms of price and time
Orders are visible to the entire market, allowing all market participants a full contribution to central market liquidity
The order book shows the number of buyers versus the number of sellers and at what price they are willing to trade
Limit orders can be entered at whatever price you choose and are available to the entire market
As limit orders are displayed publicly rather than held privately, market spreads become tighter. This benefits the order placer, giving them a better chance of getting executed at the right price; the market as a whole also benefits from a tighter public reference price to work from
You can participate in the pre-market and post-market auctions where the highest or lowest price often occurs
Regulation and market supervision by the Exchange
The order book is always available during trading hours.