Unveiled in 2009, the current Spark has proven popular in overseas markets, but has not had a major impact in the light car sector of the Australian market.
The larger Barina has been a solid seller since its 2010 unveiling, but Holden may eventually look to cut-throat pricing if a replacement is nearly four years away.
In Europe, the Spark is Chevrolet's best-selling model, and the Barina - sold there as the Chevrolet Aveo - sits third behind the larger Cruze.
The reasons behind the updated Barina's delay are unclear; but it may have to do with the outcome of recent talks between GM and the powerful Korean unions.
"The management said it originally planned to launch the redesigned Aveo in late 2015, but the plan was pushed back. It also said it will produce the new Spark in the first half of 2015," GM Korea spokesperson Choi Jong-hak told industry paper Automotive News.
The report follows news that GM has delayed the next-generation Cruze until late 2015 to carry out late engineering and styling changes.