How do you describe a right shift in supply?

Supply shifts to the right when firms are willing and able to produce more goods or services at each price point. This is caused by the non-price factors of supply (PCTWINS).

What are the factors that shift the supply curve?

The factors that shift the supply curve are the non-price factors remembered by the mnemonic PCTWINS: Productivity, Costs of production, Technology, Weather, Indirect tax, Number of firms, and Subsidies.

Y12 Microeconomics Notes

Supply | A-Level Economics Notes

Jaisul Naik

05 Feb 2026 • 1 min read

These revision notes cover everything you need to know about Supply for A-Level Economics. They're designed for students studying AQA A-Level Economics, Edexcel A-Level Economics, and Edexcel International A-Level Economics. Written by Jaisul Naik, UCL Economics graduate and A-Level Economics tutor since 2017.

What is supply?

Supply is the number of goods and services that firms are willing and able to sell at each given price.

Why is the supply curve upward sloping?

The supply curve is upward sloping (positive relationship).

At higher prices, firms are motivated to produce more of the given good or service due to higher potential profits.

Supply is also upward sloping due to the law of diminishing marginal returns (covered in year 13).