The primary difference is in scale, or quantitative. Pressure Groups (PGs) are formed to influence policies made by the govt. in the interest of its members. PGs have no intention to fight elections. ... Or to put it another way, Political Parties are attached to the government directly, whereaspressure groups aren't.

Pressure Group vs. Political Party
Pressure Group:
- A pressure group is an organized group of like-minded individuals who seek to influence public policy and decisions without directly participating in elections.
- They typically focus on specific issues or causes and aim to bring about change through lobbying, advocacy, and raising public awareness.
- Pressure groups do not field candidates or contest elections but instead work to influence policymakers and public opinion.
Political Party:
- A political party is an organized group of individuals who share similar political goals and ideologies and seek to gain and maintain political power through elections.
- Political parties develop and promote their own policy platforms, field candidates in elections, and aim to form government or influence decision-making as an opposition party.
- Political parties operate within the formal political system and participate in the electoral process to secure votes and win seats in legislative bodies.
Differences:
1. Objective: Pressure groups focus on specific issues and influencing policy, while political parties aim to gain political power through elections.
2. Participation: Pressure groups do not contest elections, while political parties actively participate in electoral politics.
3. Structure: Pressure groups are more informal and issue-based, whereas political parties have a formal structure, leadership, and party hierarchy.
4. Role: Pressure groups serve as interest intermediaries, while political parties serve as vehicles for political representation and governance.
In summary, pressure groups and political parties differ in their objectives, participation in elections, structure, and roles within the political system. Both play important roles in shaping public policy and democracy, but they operate in distinct ways to achieve their goals.