Like you, in the past I have filed all my taxes in paper form and mailed them to the IRS in Austin. It's been a real pain to be fair, especially when I made a simple error on my 2017 return that software would have picked up and corrected - it was a complex return with Capital Gains, Treaty position, AMT 1116, 5471 (shares/ownership in a foreign corporation & the subsequent disposal and capital gain) etc.The IRS have been particularly unforgiving and that return is still not finalised - lesson learned for me.
This year (2020 return) I have succumbed and resorted to using TaxAct, which I can thoroughly recommend - it handles all issues that seem to be relevant (to me at least!). You can choose to go the quick entry route and answer questions or tailor your return to manage more complex matters - here's a screenshot list of all the forms that show as available
Forms and Schedules
Form 1040 - U.S. Individual Income Tax Return
Form 1040-SS - U.S. Self-Employment Tax Return: Quick Entry Available
Form 1040-NR - U.S. Nonresident Alien Income Tax Return
Form 1040-V - Payment Voucher
Form 1040-ES - 2021 Estimated Tax Worksheet
Form 1040-ES (NR) - 2021 Estimated Tax Worksheet
Form 1040X - Amended U.S. Individual Income Tax Return
Schedule 8812 - Additional Child Tax Credit
Schedule A - Itemized Deductions
Schedule A (NR) - Itemized Deductions (Nonresident Alien)
Schedule B - Interest and Ordinary Dividends
Schedule C - Profit or Loss from Business
Schedule C-Statutory Employee - Profit or Loss from Business for Statutory Employees
Schedule D - Capital Gains and Losses
Schedule EIC - Earned Income Credit
Schedule E, Pg 1 - Supplemental Income and Loss
Schedule E, Pg 1 - Supplemental Income and Loss - Schedule K-1
Schedule E, Pg 2 - Supplemental Income and Loss
Schedule F - Profit or Loss From Farming
Schedule H - Household Employment Taxes
Schedule J - Income Averaging for Farmers and Fishermen
Schedule LEP - Request for Change in Language Preference
Schedule NEC - Tax on Income Not Effectively Connected With a U.S. Trade or Business: Quick Entry Available
Schedule OI - Other Information
Schedule R - Credit for the Elderly or the Disabled
Schedule SE - Taxpayer - Self-Employment Tax
Schedule SE - Spouse - Self-Employment Tax
Form 1045 - Application for Tentative Refund: Quick Entry Available
Form 1045 - Application for Tentative Refund Additional Forms: Quick Entry Available
Form 1045 - Schedule A--NOL: Quick Entry Available
Form 1045 - Schedule B--NOL Carryover: Quick Entry Available
Form 1116 - Foreign Tax Credit
Form 1116-AMT - Foreign Tax Credit for AMT
Form 1127 - Application for Extension of Time for Payment of Tax Due to Undue Hardship: Quick Entry Available
Form 1310 - Refund Due a Deceased Taxpayer
Form 14039 - Identity Theft Affidavit: Quick Entry Available
Form 2106 - Employee Business Expenses
Form 2120 - Multiple Support Declaration
Form 2210 - Underpayment of Estimated Tax by Individuals, Estates, and Trusts
Form 2210 - Schedule AI - Annualized Income Installment Method
Form 2210-F - Underpayment of Estimated Tax by Farmers and Fishermen
Form 2441 - Child and Dependent Care Expenses
Form 2555 - Foreign Earned Income
Form 3115 - Application for Change in Accounting Method: Quick Entry Available
Form 3468 - Investment Credit: Quick Entry Available
Form 3800 - General Business Credit
Form 3903 - Moving Expenses
Form 4136 - Credit for Federal Tax Paid on Fuels
Form 4137-Taxpayer - Tax on Unreported Tip Income
Form 4137-Spouse - Tax on Unreported Tip Income
Form 4562 - Depreciation and Amortization
Form 4563 - Exclusion of Income for Bona Fide Residents of American Samoa: Quick Entry Available
Form 4684 - Casualties and Thefts
Form 4797 - Sales of Business Property
Form 4797, Page 2 - Sales of Business Property
Form 4835 - Farm Rental Income and Expenses
Form 4868 - Application for Automatic Extension of Time to File
Form 4952 - Investment Interest Expense
Form 4972 - Taxpayer - Tax on Lump-Sum Distributions: Quick Entry Available
Form 4972 - Spouse - Tax on Lump-Sum Distributions: Quick Entry Available
Form 5074 - Allocation of Individual Income Tax to Guam or the CNMI: Quick Entry Available
Form 5329 - Taxpayer - Additional Taxes on Qualified Retirement Plans
Form 5329 - Spouse - Additional Taxes on Qualified Retirement Plans
Form 5405 - Repayment of the First-Time Homebuyer Credit
Form 5471 - Information Return of U.S. Persons with Respect to Certain Foreign Corporations: Quick Entry Available
Form 5471, Part 2 - Information Return of U.S. Persons with Respect to Certain Foreign Corporations: Quick Entry Available
Form 5695 - Residential Energy Credit
Form 5884 - Work Opportunity Credit: Quick Entry Available
Form 5884-A - Employee Retention Credit: Quick Entry Available
Form 6198 - At-Risk Limitations
Form 6251 - Alternative Minimum Tax
Form 6252 - Installment Sale Income
Form 6478 - Biofuel Producer Credit: Quick Entry Available
Form 6765 - Credit for Increasing Research Activities: Quick Entry Available
Form 6781 - Gains and Losses from Section 1256 Contracts and Straddles
Form 7202 - Taxpayer - Credits for Sick Leave and Family Leave for Self-Employed: Quick Entry Available
Form 7202 - Spouse - Credits for Sick Leave and Family Leave for Self-Employed
Form 8283 - Noncash Charitable Contributions
Form 8332 - Release/Revocation of Release of Claim to Exemption
Form 8379 - Injured Spouse Allocation
Form 8396 - Mortgage Interest Credit
Form 8453 - Tax Transmittal for E-File
Form 8582 - Passive Activity Loss Limitations
Form 8582-CR - Passive Activity Credit Limitations: Quick Entry Available
Form 8586 - Low-Income Housing Credit
Form 8594 - Asset Acquisition Statement: Quick Entry Available
Form 8606 - Taxpayer - Nondeductible IRAs
Form 8606 - Spouse - Nondeductible IRAs
Form 8609 and Form 8609-A - Low-Income Housing Credit Allocation Certification and Annual Statement
Form 8615 - Tax For Certain Children Who Have Unearned Income
Form 8621 - Return by a Shareholder of a Passive Foreign Investment Company or Qualified Electing Fund: Quick Entry Available
Form 8689 - Allocation of Individual Income Tax to the U.S. Virgin Islands: Quick Entry Available
Form 8801 - Credit for Prior Year Minimum Tax
Form 8814 - Parents' Election to Report Child's Interest and Dividends
Form 8815 - Exclusion of Interest From Series EE & I U.S. Savings Bonds Issued After 1989
Form 8820 - Orphan Drug Credit: Quick Entry Available
Form 8822 - Change of Address: Quick Entry Available
Form 8824 - Like-Kind Exchanges
Form 8826 - Disabled Access Credit: Quick Entry Available
Form 8828 - Recapture of Federal Mortgage Subsidy: Quick Entry Available
Form 8829 - Expenses for Business Use of Your Home
Form 8833 - Treaty-Based Return Position Disclosure Under Section 6114 or 7701(b): Quick Entry Available
Form 8835 - Renewable Electricity, Refined Coal, and Indian Coal Production Credit: Quick Entry Available
Form 8839 - Qualified Adoption Expenses
Form 8840 - Closer Connection Exception Statement for Aliens: Quick Entry Available
Form 8843 - Statement for Exempt Individuals and Individuals With a Medical Condition
Form 8844 - Empowerment Zone Employment Credit: Quick Entry Available
Form 8845 - Indian Employment Credit: Quick Entry Available
Form 8846 - Credit for Employer Social Security and Medicare Taxes Paid on Certain Employee Tips: Quick Entry Available
Form 8853 - Archer MSAs and LTC Insurance Contracts
Form 8862 - Information to Claim Certain Credits After Disallowance
Form 8863 - Education Credits
Form 8863, Page 2 - Education Credits
Form 8864 - Biodiesel and Renewable Diesel Fuels Credit: Quick Entry Available
Form 8874 - New Markets Credit: Quick Entry Available
Form 8880 - Credit for Qualified Retirement Savings Contributions
Form 8881 - Credit for Small Employer Pension Plan Startup Costs: Quick Entry Available
Form 8882 - Credit for Employer-Provided Childcare Facilities and Services: Quick Entry Available
Form 8885 - Taxpayer - Health Coverage Tax Credit
Form 8885 - Spouse - Health Coverage Tax Credit
Form 8888 - Allocation of Refund (Including Bond Purchases)
Form 8889 - Taxpayer - Health Savings Accounts
Form 8889 - Spouse - Health Savings Accounts
Form 8896 - Low Sulfur Diesel Fuel Production Credit: Quick Entry Available
Form 8900 - Qualified Railroad Track Maintenance Credit: Quick Entry Available
Form 8906 - Distilled Spirits Credit: Quick Entry Available
Form 8908 - Energy Efficient Home Credit: Quick Entry Available
Form 8910 - Alternative Motor Vehicle Credit: Quick Entry Available
Form 8911 - Alternative Fuel Vehicle Refueling Property Credit: Quick Entry Available
Form 8915A - Taxpayer - Qualified 2016 Disaster Retirement Plan Distributions and Repayments
Form 8915A - Spouse - Qualified 2016 Disaster Retirement Plan Distributions and Repayments
Form 8915B - Taxpayer - Qualified 2017 Disaster Retirement Plan Distributions and Repayments
Form 8915B - Spouse - Qualified 2017 Disaster Retirement Plan Distributions and Repayments
Form 8915C - Taxpayer - Qualified 2018 Disaster Retirement Plan Distributions and Repayments
Form 8915C - Spouse - Qualified 2018 Disaster Retirement Plan Distributions and Repayments
Form 8915D - Taxpayer - Qualified 2019 Disaster Retirement Plan Distributions and Repayments
Form 8915D - Spouse - Qualified 2019 Disaster Retirement Plan Distributions and Repayments
Form 8915E - Taxpayer - Qualified 2020 Disaster Retirement Plan Distributions and Repayments
Form 8915E - Spouse - Qualified 2020 Disaster Retirement Plan Distributions and Repayments
Form 8917 - Tuition and Fees Deduction
Form 8919 - Taxpayer - Uncollected Social Security and Medicare Tax on Wages
Form 8919 - Spouse - Uncollected Social Security and Medicare Tax on Wages
Form 8923 - Mine Rescue Team Training Credit: Quick Entry Available
Form 8932 - Credit for Employer Differential Wage Payments: Quick Entry Available
Form 8933 - Carbon Oxide Sequestration Credit: Quick Entry Available
Form 8936 - Qualified Plug-in Electric Drive Motor Vehicle Credit: Quick Entry Available
Form 8938 - Statement of Specified Foreign Financial Assets
Form 8941 - Credit for Small Employer Health Insurance Premiums: Quick Entry Available
Form 8949 - Sales and Other Dispositions of Capital Assets
Form 8949 Attachment - Form 8949 Attachment Summary
Form 8958 - Allocation of Tax Amounts Between Certain Individuals in Community Property States
Form 8959 - Additional Medicare Tax
Form 8960 - Net Investment Income Tax
Form 8962 - Premium Tax Credit (PTC)
Form 8990 - Limitation on Business Interest Expense Under Section 163(j): Quick Entry Available
Form 8990 Schedule A - Limitation on Business Interest Expense Under Section 163(j)
Form 8990 Schedule B - Limitation on Business Interest Expense Under Section 163(j)
Form 8995 - Qualified Business Income Deduction Simplified Computation
Form 8995-A - Qualified Business Income Deduction
Form 8995-A Schedule A - Specified Service Trades or Businesses
Form 8995-A Schedule C - Loss Netting and Carryforward
Form 8995-A Schedule D - Patron of Agricultural or Horticultural Cooperatives
Form 8997 - Initial and Annual Statement of Qualified Opportunity Fund (QOF) Investments: Quick Entry Available
Form 9465 - Installment Agreement Request
Form 965 - Inclusion of Deferred Foreign Income: Quick Entry Available
Form 965 Schedule F - Foreign Taxes Deemed Paid by Domestic Corporation: Quick Entry Available
Form 965 Schedule H - Amounts Reported on Forms 1116 and 1118 and Disallowed Foreign Taxes: Quick Entry Available
Form 965-A - Report of Net 965 Tax Liability: Quick Entry Available
Form 982 - Reduction of Tax Attributes Due to Discharge of Indebtedness
Form W-7 - Application for IRS Individual Taxpayer Identification Number: Quick Entry Available
The biggest challenge for me was buying the software with a UK credit card, but there's a workaround there also using a 'white address' of your own street address and the TaxAct office city, state and zipcode address. Worked for me, and e-filing is so much more easier - instant acknowledgement of filing receipt and tracking of refunds on line.