Will I be denied boarding if I only have a one-way ticket?

If you are a resident of the destination country or hold a long-stay visa, you will not be denied. If you are entering as a tourist, you will be denied unless you provide proof of onward travel.

Is it cheaper to book a round-trip and just skip the return flight?

Sometimes it is cheaper, but it is risky. If you skip the return leg, the airline may cancel your entire record, or flag your frequent flyer account. It is better to book one-way for moves.

Booking a one-way flight for an international move

Booking a one-way international flight requires showing proof of onward travel or a valid long-stay visa to airline staff. Always purchase tickets directly through the airline's website to avoid third-party agency restrictions that can complicate itinerary changes during a move.

Verify visa requirements. Before booking, confirm your entry status. If you are moving on a tourist visa initially, you must purchase a 'throwaway' onward ticket or use a rental service like OnwardTicket to provide proof of departure, otherwise, the check-in agent will deny boarding.
Search via Google Flights. Use the Google Flights matrix set to 'One-way' to identify routes. Filter by 'Non-stop' to minimize the risk of luggage loss or customs complications during transit.
Book directly with the carrier. Once you find the flight, go to the airline's official website. Never use an OTA (Online Travel Agency) for one-way moves; if your flight is delayed or you need to change your date, the airline will not assist you if the ticket was issued by a third party.
Maximize baggage allowance. Since you are moving, upgrade to a 'Plus' or 'Flex' economy fare. This usually includes 2 checked bags (up to 23kg each) instead of the standard 1, which is cheaper than paying for excess baggage at the airport counter.

Will I be denied boarding if I only have a one-way ticket?: If you are a resident of the destination country or hold a long-stay visa, you will not be denied. If you are entering as a tourist, you will be denied unless you provide proof of onward travel.
Is it cheaper to book a round-trip and just skip the return flight?: Sometimes it is cheaper, but it is risky. If you skip the return leg, the airline may cancel your entire record, or flag your frequent flyer account. It is better to book one-way for moves.