Boeing has agreed a deal with Iran Aseman Airlines for 30 Boeing 737 Max planes for $3bn (£2.4bn), with deliveries starting from 2022.
The agreement, marking its first plane sale to Iran under President Trump, also provides the airline with purchase rights for 30 additional planes.
According to the US department of commerce, an aerospace sale of this size creates or sustains around 18,000 jobs in the US.
There had been uncertainty over the new administration's tolerance for US business dealings in Iran. Boeing had previously agreed a $16.6bn sale in Iran after the nuclear deal struck with Tehran under the Obama administration, something Trump has been a vocal critic of.
Boeing said it had negotiated the memorandum of agreement under authorisation from the US government, "following a determination that Iran had met its obligations under the nuclear accord signed in 2015".
Iran's deal with world powers, limiting its enrichment of uranium in return for the removal of some international sanctions, allowed for the purchase of aircraft and parts.
The aerospace giant said it continued to follow the lead of the US government with regards to working with Iran's airlines and any contracts with the carriers are contingent upon government approval.
At the very beginning of Trump's presidency, some of his policy announcements had caused uncertainty for the company; risking disrupting business relations with China which is Boeing's biggest single jetliner customer.
And in December, Trump tweeted threatening to cancel plans for new presidential jets. Boeing chief executive Dennis Muilenburg reached out to the President and has since developed closer ties.
Boeing is building a brand new 747 Air Force One for future presidents, but costs are out of control, more than $4 billion. Cancel order!— Donald J. Trump (@realDonaldTrump) December 6, 2016
The President visited Boeing's campus in South Carolina in February to attend the unveiling of Boeing's new 787-10 Dreamliner, cementing more positive relations.