Oleg Bogdanov, Oleksander Kozak and Oleksii Pavliuchenko were stopped by Border Force officers as they attempted to bring the would-be migrants into the country using the isolated Suffolk quay.
The trio were sentenced to four years, three years four months and two years four months respectively when they appeared at Ipswich Crown Court on 1 October. They had all pleaded guilty to conspiring to facilitate a breach of the UKs immigration laws at an earlier hearing.
Pavliuchenko, 21, and Bogdanov, 41, both of no fixed UK address, were the crew on board a yacht that transported six Ukrainian nationals five men and a woman into Orford Quay in the early hours of 3 July.
Kozak, 25, who also admitted falsely possessing a Polish driving licence, was waiting for them in a people carrier on the quayside.
Alongside Kozak in the vehicle was Tanye Boginska, 24. Boginska, whose name was also given as Tatiana Scharban in court, admitted falsely possessing a Lithuanian ID card and was jailed for 12 months.
As the immigration offenders stepped into the car at Orford Quay, Border Force officers who had been monitoring events on CCTV moved in, assisted by Home Office Immigration Enforcement investigators.
Kozak, Boginska and the six Ukrainians were arrested on the quayside.
The yacht was intercepted in the estuary by Border Force Cutter Searcher and escorted back to Orford Quay where Pavliuchenko and Bogdanov were arrested.
An investigation was launched by the Home Offices Criminal Investigations Team which resulted in the conviction of the plotters.
The six Ukrainians brought into the UK as part of the plot have been removed from the country.
Phillip Holliday, Border Force Regional Director, said:
These smugglers thought that because they were operating at night and because they were targeting a small quay their offences would go undetected. They were wrong.
The message this case sends out couldnt be clearer. No matter what route criminals take to try and breach our border controls, we have the capability to stop them.
Border Force officers, and our fleet of cutters, play a key role in preventing people smuggling and illegal immigration as well as intercepting shipments of drugs and other prohibited goods.
Inspector Andy Radcliffe, from the Home Offices Criminal Investigations Team, said:
Where we have information about suspected illegal immigration we act on it swiftly. Anyone involved in this kind of criminality should know we will catch them and when we do as these sentences show - the consequences are considerable.
Pavliuchenko, Bogdanov, Kozak and Boginska will all be automatically considered for deportation at the end of their sentences.
The Criminal Investigations Team consists of warranted Home Office Immigration Enforcement officers working alongside seconded police officers to investigate organised immigration crime.
Anyone who has information on suspected immigration offenders can visit
Anyone with information about activity they suspect may be linked to smuggling can call our hotline on 0800 59 5000.