So far we have three seasons and thirteen episodes. Some are better than others but I wouldn't say any episodes have been outright bad (no lower than a 6/7 out of 10). Here's my ranking from best to "worst":
Fifteen Million Merits
The Entire History of You
San Junipero
Be Right Back
White Bear
Shut Up and Dance
Nosedive
White Christmas
Playtest
Hated in the Nation
The National Anthem
Men Against Fire
The Waldo Moment
I seem to have a bit of a different ranking, maybe I watched season 1 in the wrong mood.
White Christmas
Shut Up and Dance
Be Right Back
White Bear
Nosedive
Men Against Fire
Hated In The Nation
Playtest
San Junipero
The Waldo Moment
The National Anthem
Fifteen Million Merits
The Entire History of You
Nosedive
Shut Up and Dance
White Christmas
National Anthem
The Entire History of You
Fifteen Million Merits
Men Against Fire
Be Right Back
Hated in the Nation
Playtest
White Bear
San Junipero
The Waldo Moment
My best to worst list
Shut up and dance
San Junipero
White bear
The Entire History of You
White Christmas
Hated in the Nation
National Anthem
Nosedive
Be Right Back
15 Million Merits
Man Against Fire
Playtest
The Waldo Moment
White Bear
Shut Up and Dance
Hated in the Nation
Men Against Fire
White Christmas
San Junipero
Fifteen Million Merits
The Entire History of You
Be Right Back
Playtest
Nosedive
The National Anthem
The Waldo Moment