Under the new agreement, the European Union's existing emissions trading scheme market will be broadened to include sea and air transport.
Carbon from individuals' vehicles and homes will also be counted, though at a capped level until 2030.
And a special 88-billion-euro ($97 billion) social climate fund will be created in 2026 to compensate for the cost of Europe's green shift.
The incoming legislation supports the EU goal of cutting 55 percent of greenhouse gas emissions in the bloc by 2030, compared to the levels recorded in 1990.
One measure that will be seen by companies importing into the EU will be a carbon tax on imports, phased in from 2026 and levied to ensure EU industries are not undercut by firms not facing the same added costs.
It will initially cover the most polluting sectors - producers of steel, aluminum, cement, fertilizer and electricity - and could be expanded in the future to organic chemicals and polymers.
The tax - called an "adjustment" in Brussels-speak - is expected to raise as much as 14 billion euros a year for the EU budget.
The sign-off, in a Luxembourg meeting of EU agriculture ministers, endorses a European Parliament vote last week on various legislative texts in the reform, which will come into force once published.