If I have filed for a divorce but it’s still pending can I file as single?

No, if you are still legally married, you cannot file as Single. 

If you were legally married at the end of 2023 your filing choices are married filing jointly or married filing separately.   Or.....if you have been separated from your spouse for at least the last six months of 2023 AND you are the custodial parent of the children, you might be able to file as Head of Household.  Filing Single is not a choice.

Married Filing Jointly is usually better, even if one spouse had little or no income. When you file a joint return, you and your spouse will get the married filing jointly standard deduction of $27,700 (+$1500 for each spouse 65 or older)  You are eligible for more credits including education credits, earned income credit, child and dependent care credit, and a larger income limit to receive the child tax credit. 

If you choose to file married filing separately, both spouses have to file the same way—either you both itemize or you both use standard deduction. Your tax rate will be higher than on a joint return.

 Some of the special rules for filing separately include: you cannot get earned income credit, education credits, adoption credits, or deductions for student loan interest. A higher percent of your Social Security benefits may be taxable. Your limit for SALT (state and local taxes and sales tax) will be only $5000 per spouse. In many cases you will not be able to take the child and dependent care credit. The amount you can contribute to a retirement account will be affected. If you live in a community property state, you will be required to provide additional information regarding your spouse’s income. ( Community property states:  AZ, CA, ID, LA, NV, NM, TX, WA, WI)

 If  you are using online TurboTax to prepare your returns, you will need to prepare two separate returns and pay twice since with online, you get one return per fee.

https://ttlc.intuit.com/questions/1894449-married-filing-jointly-vs-married-filing-separately

https://ttlc.intuit.com/questions/1901162-married-filing-separately-in-community-property-states

https://ttlc.intuit.com/questions/1894449-is-it-better-for-a-married-couple-to-file-jointly-or-separately

Am I Head of Household?

https://ttlc.intuit.com/questions/1894553-do-i-qualify-for-head-of-household

https://ttlc.intuit.com/questions/2900097-what-is-a-qualifying-person-for-head-of-household

If you qualify as Head of Household, when you enter your marital status (single or married filing separately) into MyInfo, and then enter your qualifying dependent, TurboTax will offer HOH as your filing status.

If you are still legally married as of 12/31/2023 then on your 2023 tax return you can only file as either Married Filing Jointly or Married Filing Separately.

Unless you have not lived with your spouse as any time during the last six months of 2023 And you have a child as a dependent then you may be able to file as Head of Household - https://ttlc.intuit.com/turbotax-support/en-us/help-article/taxation/married-person-claim-head-household-filing-status/L078u1RSW_US_en_US?uid=lqwzs81h