[pc86]

> In the US something like 80% of tax returns could be calculated by the government on behalf of the tax payer, but for whatever reason that hasn't been implemented.

The reason is that the USG doesn't have a prior knowledge of material facts that may change your return, most notably deductions and charitable donations (especially small monetary donations, in-kind contributions, used goods such as clothing, etc). You're probably right that a vast majority of returns could be accurately calculated on January 1 because they don't have a 10K, Schedules A or C, but they don't know which returns fall into that category.

Simplification of the tax code could go a long way toward increasing that percentage but I'm not sure it could ever be enough to have the government simply tabulate a bill or refund for every citizen.

[count]

The reason is that the income tax prep industry has lobbied intensely to avoid a 'if you don't file, well just use your defaults on a 1040 that we would charge you with anyways' as your filing.

For most 40-hr/wk, full time employees with one job, they should net a '0' refund, and the return should be automatically completed based on their employers weekly/quarterly filing of payroll tax records.

[pc86]

> For most 40-hr/wk, full time employees with one job, they should net a '0' refund, and the return should be automatically completed based on their employers weekly/quarterly filing of payroll tax records.

Only with eliminating the distinction between the standard and itemized deductions, and only for employees who work no overtime and earn no bonus. Who also don't have any post-tax activities that affect their tax liability (IRA contributions outside of an employer-sponsored 401(k), charitable contributions, 529 plan contributions). Who also don't have any out-of-pocket healthcare expenses beyond that threshold.

[count]

Most 40-hr/wk full time employees don't make overtime. And bonuses are usually/always taxed. And with the recent change in things, the threshold at which itemization becomes worth while has become significant.

Most. Not all. None of your exceptions changes things. The IRS should assume a net-0 based on tax records, and if the person wants to do something else, they're free to file a return.