Missing EI connection
 

I have a flight booked on a thru ticket to SFO that starts in Ireland with Aer Lingus to LHR and onto SFO. Unusually the flight number UA.COM has booked me on is an EI flight number not a UA codeshare flight number. My question if I miss the EI flight will my UA flight get cancelled. I know on a UA codeshare it would but have never been ticketed on EI flight number.

Thanks :p

Codeshare or not is irrelevant. If you miss the first flight, the remainder of your itinerary will be cancelled.

To be precise, the remaining segments of the ticket will be cancelled. The ticket will retain whatever value, if any, the fare conditions provide and you may then purchase a new ticket less any penalties. The cost could be anywhere from 0 to a new ticket at walk-up prices.