In the previous plans, it was assumed that the church tax share for the church communities would be around 280 to 290 million euros in the long term.
This assumption is no longer tenable, the diocese said on Monday.
Instead, in terms of church communities, only church tax revenues of about 260 million euros for the year 2026 and only around 246 million euros in 2027 can be expected.
At the same time, the diocese referred to its own financial planning, according to which an "annual structural financing deficit of around 65 million euros by the year 2035" is to be expected.
The reason for this is rising personnel and material costs, in particular as a result of wage and price increases.
It has been known for some time that the diocese and its parishes will have fewer church tax funds available in the future. The diocese and the parishes are entitled to the distributable church tax revenue in half each.
In the recently published "Updated Budget Decree 2025/2026", the diocese has now informed about the decision of the Diocesan Council of November 2025 to reduce the church tax allocation to the church communities by 8.7 percent.
'Baby boomers' retire
One cause of the falling church tax revenues, according to the diocese, is "the persistently difficult economic situation."
This is also noticeable in Württemberg, which is strongly influenced by the currently weakening sectors of mechanical engineering and the automotive industry.
In addition, there are a declining number of baptisms and a persistently high number of church disputes. Moreover, the income-driven "baby boomer" generation is retiring.
The diocese of Rottenburg-Stuttgart, with its 1,020 parishes and around 1.6 million members, comprises the Württemberg district of Baden-Württemberg.
It is the third largest diocese in Germany.
In the future, the merger of the current 1,020 parishes into 50 to 80 new parishes is to be used to reduce the administrative burden to the administration.
According to Bishop Klaus Krämer, the goal is that all planned 50 to 80 larger units have been formed in 2030.