How Does a Very Deep ITM Option’s Theta Compare to an ATM Option?

A very deep In-The-Money (DITM) option's Theta is significantly lower than an At-The-Money (ATM) option's Theta. DITM options have very little time value to lose, as their value is mostly intrinsic, whereas ATM options have the maximum time value.

Does an In-the-Money Option Experience Less Time Decay than an Out-of-the-Money Option?
What Is a “Deep In-the-Money” Option?
How Does an ATM Put option’S Premium Compare to an ATM Call Option’s Premium?
How Does Gamma Behave for a DITM Option?
Why Do DITM Options Have Less Time Value than ATM Options?
How Does Gamma Affect a DITM Option?
Why Does a Deep-in-the-Money Option Have Very Little Extrinsic Value?
How Does Theta Affect Deep In-the-Money Options versus At-the-Money Options?

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