Allow a Text Box to Grow or Shrink (Report Builder and SSRS)
Applies To: SQL Server 2016
By default, text boxes are a fixed size. You can set options that let the text box expand or shrink based on its contents. These options correspond to the CanGrow or CanShrink properties in the Properties pane.
Right-click the text box and click Text Box Properties.
Click the General tab.
To allow the text box to expand vertically based on its contents, select Allow height to increase.
To allow the text box to shrink based on its contents, select Allow height to decrease.