The senior Democratic Unionist Party MP has apologised for the “unintentional failure” to register the hospitality, which he estimated was worth over £50,000.
The sanction, if approved by the Commons, could have an effect on crucial Brexit votes as Theresa May will have one fewer of the 10 DUP MPs propping up her minority government.
The parliamentary commissioner for standards, which is recommending the suspension, said the cost of the luxury trips may be “significantly more”, with reports claiming it could be closer to £100,000.
It said the Sri Lankan trips in 2013 included business-class air travel, accommodation at first-class hotels, helicopter trips and visits to tourist attractions for the North Antrim MP and his family.
“In view of the seriousness of this matter, we recommend that Mr Paisley be suspended from the service of the House for a period of 30 sitting days starting on 4 September 2018,” the watchdog’s findings read.
The sanction was outlined by the House of Commons standards committee following receipt of the findings.
The committee said Mr Paisley, son of late DUP founder the Reverend Ian Paisley, had committed “serious misconduct” and his actions “were of a nature to bring the House of Commons into disrepute”.
Mr Paisley could face a by-election over the sanction – as members who are suspended from the Commons for more than 10 days are open to a recall petition.
The by-election would occur if 10% of the electorate in Mr Paisley’s North Antrim constituency sign the petition.
Sinn Fein has called on Mr Paisley to quit. The party’s Foyle MP Elisha McCallion said: “Ian Paisley Jnr should step down and resign with immediate effect.
“If he is not prepared to do the right thing then the DUP must demand his resignation.”
She added: “If Ian Paisley or the DUP do not do the right thing then it is entirely legitimate for the electorate of North Antrim to exercise its right to force a by-election.”
Mr Paisley should now register the holidays with the parliamentary authorities, the parliamentary commissioner for standards said.
The trips also included meeting Sri Lankan governmental figures in what the report described as “serious misconduct”.
His actions “were of a nature to bring the House of Commons into disrepute,” it added.
The suspension is set to last 30 sitting days and begin on 4 September. Mr Paisley’s break could last until mid-November since parliament breaks over the party conference season.
A statement issued by Mr Paisley’s lawyer said: “My client has apologised unreservedly at the outset for his unintentional failure to register the hospitality he received.”