This is what we import from the US. If we imposed tariffs on them to match those imposed on goods the US imports from us I'm not sure how much our cost of living would be affected in the short term.
The UK imported £19.9 billion of machinery and transport equipment imports from the United States in 2023, comprising 9.2% of all imports of this commodity (Figure 1). Machinery and transport equipment includes various components, including mechanical machinery, engines, aircraft and cars. The largest commodities imported were £5.5 billion of mechanical power generators (intermediate) and £3.1 billion of aircraft (Table 1).
The UK imported £18.7 billion of fuels from the United States in 2023, comprising 23.5% of all imports of this commodity. This primarily included £8.5 billion of crude oil (unrefined petroleum which is then refined to produce useable products such as petrol or diesel), and £6.6 billion of natural gas.
There were £7.8 billion of chemical imports from the United States in 2023, accounting for 11.2% of all imports of this commodity. Imports of medicinal and pharmaceutical products made up approximately half (£3.8 billion) of the UK's imports of chemicals from the United States. This includes medicines such as vitamins, antibiotics and vaccines as well as products such as bandages, wadding and gauze for use in medical, surgical or dental settings.
Details of our exports to the US can be found on this page, too. Perhaps someone else might be able to detail the implications for the UK? I would think that US tariffs would increase costs to US consumers, leading to a drop in demand for UK goods and services.
www.ons.gov.uk/economy/nationalaccounts/balanceofpayments/articles/uktradewiththeunitedstates2023/2023