The Immigrant Council of Ireland has said an all-island approach on sex laws would give pimps no refuge.
It comes as politicians in Stormont bid to make paying for sex illegal in the North.
The crackdown on prostitution is part of a range of measures contained in draft legislation aimed at tackling human trafficking and exploitation in Northern Ireland.
While activities such as kerb-crawling, pimping and brothel-keeping are illegal in the UK, selling or paying for sex is permitted.
Denise Charlton, chief executive of the Immigrant Council of Ireland, said the proposed law reform should provide an all-island approach to putting pimps, traffickers and other criminals out of business.
The group, which is spearheading the Turn Off the Red Light Campaign to bring in the same law change in the Republic of Ireland, said the initiative should bring urgency to the debate.
Ms Charlton said: "Criminals and in particular those behind the sex trade ignore borders and do not see them as obstacles. By bringing the laws on both parts of Ireland into line we would be sending a powerful message that this industry and its exploitation is not welcome here.
"It is also important to note that the Northern Ireland Consultation is drawing attention to the experience in Sweden where payments for sex have been outlawed for over a decade. This is also the example we are using to bring about change in the South."
As well as the ban on buying sex, the North's Human Trafficking and Exploitation Bill proposes to:
:: Allow courts to take aggravating factors into consideration when passing sentence;
:: Extend the definition of “other exploitation” to include forced begging;
:: Define what is a victim of trafficking;
:: Introduce compensation procedures for victims;
:: Ensure child victims have a legal advocate to support them through the relevant criminal, immigration and compensation procedures;
:: Provide “special measures” for trafficking victims if they act as witnesses;
:: Set out what assistance and support as well as civil legal services are required and available to victims of trafficking;
:: Ensure no prosecution is brought for a criminal offence committed by a trafficking victim as a direct consequence of being trafficked;
:: Require training and investigative tools to be made available for police and prosecutors;
:: Require Stormont’s Department of Justice to produce an annual strategy on raising awareness and reducing trafficking in human beings.
The public consultation period ends on October 18.