Change Bar Chart Title Font Size in Matplotlib

A sales manager sent me a quarterly bar chart last month with one complaint: the title looked like a footnote next to the bars.

In this tutorial, I’ll change the matplotlib bar chart title font size on one chart, on every chart, and on a grid of bar charts.

Quick answer: pass fontsize to ax.set_title() (or plt.title()). Numbers are points; words like "x-large" scale from the base font:

ax.set_title("Q1 2026 Sales by Region", fontsize=20)

Every number below came from real runs on Matplotlib 3.11.2 and Python 3.12.5.

Sample Data for the Bar Chart Title Examples

All examples share one file, region_sales.py, with made-up 2026 regional sales in USD. If Matplotlib isn’t there yet, install Matplotlib first.

regions = ["Northeast", "Southeast", "Midwest", "Southwest", "West"]
q1_sales = [184250.75, 162480.40, 139915.20, 121730.95, 205640.10]
q2_sales = [191870.30, 170215.85, 144060.50, 133415.25, 214980.65]

if __name__ == "__main__":
    for r, s in zip(regions, q1_sales):
        print(f"{r:<10} ${s:,.2f}")

Output:

Northeast  $184,250.75
Southeast  $162,480.40
Midwest    $139,915.20
Southwest  $121,730.95
West       $205,640.10

Change the Bar Chart Title Font Size with fontsize

The default title is 12 points, because axes.titlesize is "large" (1.2 times the 10-point base). Passing fontsize=20 replaces it:

import matplotlib.pyplot as plt
from region_sales import regions, q1_sales

fig, ax = plt.subplots(figsize=(7, 4), layout="constrained")
ax.bar(regions, [s / 1000 for s in q1_sales], color="#2F6DB5")
ax.set_ylabel("Sales (thousand USD)")
ax.set_title("Q1 2026 Sales by Region")
print("rcParams axes.titlesize:", plt.rcParams["axes.titlesize"])
print("Default title size:", ax.title.get_fontsize())

ax.set_title("Q1 2026 Sales by Region", fontsize=20)
print("After fontsize=20:", ax.title.get_fontsize())
plt.show()

Output:

rcParams axes.titlesize: large
Default title size: 12.0
After fontsize=20: 20.0

My Matplotlib title font size guide covers titles on every plot type.

How Do I Make a Bar Chart Title Bold and Larger at Once?

Same bars, now with fontdict, which bundles size, weight, family and color, while loc and pad move the title:

import matplotlib.pyplot as plt
from region_sales import regions, q1_sales

title_font = {"fontsize": 18, "fontweight": "bold",
              "family": "serif", "color": "#1B3A5C"}

fig, ax = plt.subplots(figsize=(7, 4), layout="constrained")
ax.bar(regions, [s / 1000 for s in q1_sales], color="#2F6DB5")
ax.set_ylabel("Sales (thousand USD)")
t = ax.set_title("Q1 2026 Sales by Region", fontdict=title_font,
                 loc="left", pad=14)
print(t.get_fontsize(), t.get_fontweight(), t.get_family())
plt.show()

Output:

18.0 bold ['serif']

To restyle the bar values too, see Matplotlib bar chart labels.

Set the Title Font Size for Every Bar Chart with rcParams

For many charts, plt.rc_context() changes axes.titlesize only inside the with block:

import matplotlib.pyplot as plt
from region_sales import regions, q1_sales

for size in ["medium", "x-large", 22]:
    with plt.rc_context({"axes.titlesize": size}):
        fig, ax = plt.subplots()
        ax.bar(regions, q1_sales)
        ax.set_title("Q1 2026 Sales by Region")
        pt = round(ax.title.get_fontsize(), 1)
        print(f"axes.titlesize={size!r:<10} -> {pt} pt")
    plt.close(fig)

Output:

axes.titlesize='medium'   -> 10.0 pt
axes.titlesize='x-large'  -> 14.4 pt
axes.titlesize=22         -> 22.0 pt

Note that "x-large" works out to 14.4 points. Tick labels ignore this setting; use tick_params for tick font size instead.

Change Subplot and suptitle Font Sizes on Bar Charts

Each axes gets its own set_title(), and fig.suptitle() sizes the overall title separately:

import matplotlib.pyplot as plt
from region_sales import regions, q1_sales, q2_sales

fig, (ax1, ax2) = plt.subplots(1, 2, figsize=(10, 4),
                               sharey=True, layout="constrained")
ax1.bar(regions, [s / 1000 for s in q1_sales], color="#2F6DB5")
ax2.bar(regions, [s / 1000 for s in q2_sales], color="#E07B39")
ax1.set_title("Q1 2026", fontsize=14)
ax2.set_title("Q2 2026", fontsize=14)
ax1.set_ylabel("Sales (thousand USD)")
for ax in (ax1, ax2):
    ax.tick_params(axis="x", labelrotation=30)

sup = fig.suptitle("Sales by Region, First Half of 2026",
                   fontsize=20, fontweight="bold")
print("Subplot titles:", ax1.title.get_fontsize(), ax2.title.get_fontsize())
print("suptitle:", sup.get_fontsize())
plt.show()

Output:

Subplot titles: 14.0 14.0
suptitle: 20.0

suptitle() follows figure.titlesize, not axes.titlesize. For bold subplot titles in bigger grids, read subplot title font size and bold.

Common Errors with Bar Chart Title Font Size

I hit all three of these on client work:

import matplotlib.pyplot as plt
from region_sales import regions, q1_sales

fig, ax = plt.subplots()
ax.bar(regions, q1_sales)

try:
    ax.set_title("Q1 2026 Sales", fontsize="huge")
except ValueError as err:
    print("ValueError:", str(err).split(".")[0])

ax.set_title("Q1 2026 Sales")
plt.rcParams["axes.titlesize"] = 24
print("Existing title:", ax.title.get_fontsize())

plt.title = "Q1 2026 Sales"
try:
    plt.title("Q1 2026 Sales", fontsize=18)
except TypeError as err:
    print("TypeError:", err)

Output:

ValueError: Size is invalid
Existing title: 12.0
TypeError: 'str' object is not callable

Valid names run from "xx-small" to "xx-large". Set rcParams before creating the chart, and restart the kernel if plt.title got overwritten. The same fixes apply to pie chart title font size.

You might also find these useful:

• Titles for each subplot and an overall title
• Change the Matplotlib legend font size
• Matplotlib x-axis label
• Save a Matplotlib chart as PNG

Frequently asked questions