diff --git a/README.md b/README.md
index b967929..bc0a110 100644
--- a/README.md
+++ b/README.md
@@ -99,7 +99,7 @@ It is recommended that the alerts channel be registered and monitored.
 * **`blacklist/title`**: This is a list of strings. If a title is one of these strings, it is not posted.
 The comparison is case insensitive.
 * **`blacklist/url`**: This is a list of strings. If a URL is one of these strings, its title is not posted.
-The comparison is case sensitive.
+The comparison is case insensitive.
 * **`ignores`**: This is a list of nicks to ignore.
 * **`mode`**: This can for example be `+igR` for [Freenode](https://freenode.net/kb/answer/usermodes).
 Setting it is recommended.
diff --git a/ircurltitlebot/__main__.py b/ircurltitlebot/__main__.py
index ea764e7..191db08 100644
--- a/ircurltitlebot/__main__.py
+++ b/ircurltitlebot/__main__.py
@@ -50,6 +50,7 @@ def load_config() -> None:
     blacklists["title"] = set(blacklists.get("title", set()))
     blacklists["title"] = {entry.casefold() for entry in blacklists["title"]}
     blacklists["url"] = set(blacklists.get("url", set()))
+    blacklists["url"] = {entry.casefold() for entry in blacklists["url"]}
 
     config.INSTANCE = instance_config
 
diff --git a/ircurltitlebot/bot.py b/ircurltitlebot/bot.py
index 0b27194..3ce086f 100644
--- a/ircurltitlebot/bot.py
+++ b/ircurltitlebot/bot.py
@@ -237,7 +237,7 @@ def _handle_privmsg(irc: miniirc.IRC, hostmask: Tuple[str, str, str], args: List
     urls = [url[0] for url in itertools.groupby(urls)]  # Guarantees consecutive uniqueness. https://git.io/fjeWl
     # urls = [url for url in urls if not re.fullmatch(r'[^@]+@[^@]+\.[^@]+', url)]  # Skips emails. https://git.io/fjeW3
     urls = [url for url in urls if urlparse(url).scheme not in ("file", "git")]  # Alt: scheme in ('http', 'https', '')
-    urls = [url for url in urls if url not in config.INSTANCE["blacklist"]["url"]]
+    urls = [url for url in urls if url.casefold() not in config.INSTANCE["blacklist"]["url"]]
     if urls:
         urls_str = ", ".join(urls)
         log.debug("Incoming message from %s in %s has %s URLs to process: %s", user, channel, len(urls), urls_str)