@Chris-Kawa This worked, thank you very much!

Code wise using:

QGroupBox *groupBox = new QGroupBox(tr("My Group Box")); QGridLayout *layout = new QGridLayout(groupBox); layout->addWidget(new QPushButton(tr("My Nice Button")), 0, 0); layout->setColumnStretch(0, 1); layout->setColumnStretch(1, 1);

does what you want.