Mark J. Sokolowski, MD Sc
Plan context: Mark J. Sokolowski, MD Sc 401(K) Plan
EIN 26-3499165 • Oak Park, IL • 25 filings • 2 plans
Current Snapshot
Latest Year
2025
2025 Participants
8
2025 Assets
$1,913,107
2025 Contributions
$90,369
Historical Graphs
Total Assets Over Time
Aggregate end-of-year assets by filing year, excluding zero-asset years
Participants Over Time
Largest reported end-of-year plan headcount by filing year, used to avoid double-counting participants across overlapping plans
Company Timeline
Year summaries and individual filings are combined here so you can stay in one place while moving across years and plan filings.
| Year / Filing | Filings | Participants | Assets | Contributions | Contrib./Participant |
|---|---|---|---|---|---|
| 2025 | 1 | 8 | $1,913,107 | $90,369 | $11,296iApproximate average salary by contribution assumption: employee only about $282,403 at 4% or $188,269 at 6%; with 50% employer match about $188,269 at 4% or $125,513 at 6%; with 100% employer match about $141,202 at 4% or $94,134 at 6%. |
| Mark J. Sokolowski, MD Sc 401(K) Plan | - | 8 | $1,913,107 | $90,369 | $11,296iApproximate average salary by contribution assumption: employee only about $282,403 at 4% or $188,269 at 6%; with 50% employer match about $188,269 at 4% or $125,513 at 6%; with 100% employer match about $141,202 at 4% or $94,134 at 6%. |
| 2024 | 2 | 8 | $3,436,834 | $68,485 | $8,561iApproximate average salary by contribution assumption: employee only about $214,016 at 4% or $142,677 at 6%; with 50% employer match about $142,677 at 4% or $95,118 at 6%; with 100% employer match about $107,008 at 4% or $71,339 at 6%. |
| MARK J. SOKOLOWSKI, M.D., S.C. CASH BALANCE PLAN | - | 4 | $2,035,492 | $0 | - |
| Mark J. Sokolowski, MD Sc 401(K) Plan | - | 8 | $1,401,342 | $68,485 | $8,561iApproximate average salary by contribution assumption: employee only about $214,016 at 4% or $142,677 at 6%; with 50% employer match about $142,677 at 4% or $95,118 at 6%; with 100% employer match about $107,008 at 4% or $71,339 at 6%. |
| 2023 | 2 | 6 | $2,815,477 | $317,872 | $52,979iApproximate average salary by contribution assumption: employee only about $1,324,467 at 4% or $882,978 at 6%; with 50% employer match about $882,978 at 4% or $588,652 at 6%; with 100% employer match about $662,233 at 4% or $441,489 at 6%. |
| MARK J. SOKOLOWSKI, M.D., S.C. CASH BALANCE PLAN | - | 5 | $1,732,372 | $264,257 | $52,851iApproximate average salary by contribution assumption: employee only about $1,321,285 at 4% or $880,857 at 6%; with 50% employer match about $880,857 at 4% or $587,238 at 6%; with 100% employer match about $660,643 at 4% or $440,428 at 6%. |
| Mark J. Sokolowski, MD Sc 401(K) Plan | - | 6 | $1,083,105 | $53,615 | $8,936iApproximate average salary by contribution assumption: employee only about $223,396 at 4% or $148,931 at 6%; with 50% employer match about $148,931 at 4% or $99,287 at 6%; with 100% employer match about $111,698 at 4% or $74,465 at 6%. |
| 2022 | 2 | 6 | $2,111,908 | $482,356 | $80,393iApproximate average salary by contribution assumption: employee only about $2,009,817 at 4% or $1,339,878 at 6%; with 50% employer match about $1,339,878 at 4% or $893,252 at 6%; with 100% employer match about $1,004,908 at 4% or $669,939 at 6%. |
| MARK J. SOKOLOWSKI, M.D., S.C. CASH BALANCE PLAN | - | 4 | $1,276,899 | $400,000 | $100,000iApproximate average salary by contribution assumption: employee only about $2,500,000 at 4% or $1,666,667 at 6%; with 50% employer match about $1,666,667 at 4% or $1,111,111 at 6%; with 100% employer match about $1,250,000 at 4% or $833,333 at 6%. |
| Mark J. Sokolowski, MD Sc 401(K) Plan | - | 6 | $835,009 | $82,356 | $13,726iApproximate average salary by contribution assumption: employee only about $343,150 at 4% or $228,767 at 6%; with 50% employer match about $228,767 at 4% or $152,511 at 6%; with 100% employer match about $171,575 at 4% or $114,383 at 6%. |
| 2021 | 2 | 6 | $1,968,452 | $155,177 | $25,863iApproximate average salary by contribution assumption: employee only about $646,571 at 4% or $431,047 at 6%; with 50% employer match about $431,047 at 4% or $287,365 at 6%; with 100% employer match about $323,285 at 4% or $215,524 at 6%. |
| MARK J. SOKOLOWSKI, M.D., S.C. CASH BALANCE PLAN | - | 4 | $1,033,848 | $83,000 | $20,750iApproximate average salary by contribution assumption: employee only about $518,750 at 4% or $345,833 at 6%; with 50% employer match about $345,833 at 4% or $230,556 at 6%; with 100% employer match about $259,375 at 4% or $172,917 at 6%. |
| Mark J. Sokolowski, MD Sc 401(K) Plan | - | 6 | $934,604 | $72,177 | $12,030iApproximate average salary by contribution assumption: employee only about $300,738 at 4% or $200,492 at 6%; with 50% employer match about $200,492 at 4% or $133,661 at 6%; with 100% employer match about $150,369 at 4% or $100,246 at 6%. |
| 2020 | 2 | 6 | $1,558,814 | $164,986 | $27,498iApproximate average salary by contribution assumption: employee only about $687,442 at 4% or $458,294 at 6%; with 50% employer match about $458,294 at 4% or $305,530 at 6%; with 100% employer match about $343,721 at 4% or $229,147 at 6%. |
| MARK J. SOKOLOWSKI, M.D., S.C. CASH BALANCE PLAN | - | 5 | $843,638 | $85,738 | $17,148iApproximate average salary by contribution assumption: employee only about $428,690 at 4% or $285,793 at 6%; with 50% employer match about $285,793 at 4% or $190,529 at 6%; with 100% employer match about $214,345 at 4% or $142,897 at 6%. |
| Mark J. Sokolowski, MD Sc 401(K) Plan | - | 6 | $715,176 | $79,248 | $13,208iApproximate average salary by contribution assumption: employee only about $330,200 at 4% or $220,133 at 6%; with 50% employer match about $220,133 at 4% or $146,756 at 6%; with 100% employer match about $165,100 at 4% or $110,067 at 6%. |
| 2019 | 2 | 6 | $1,267,671 | $162,455 | $27,076iApproximate average salary by contribution assumption: employee only about $676,896 at 4% or $451,264 at 6%; with 50% employer match about $451,264 at 4% or $300,843 at 6%; with 100% employer match about $338,448 at 4% or $225,632 at 6%. |
| MARK J. SOKOLOWSKI, M.D., S.C. CASH BALANCE PLAN | - | 5 | $733,773 | $84,225 | $16,845iApproximate average salary by contribution assumption: employee only about $421,125 at 4% or $280,750 at 6%; with 50% employer match about $280,750 at 4% or $187,167 at 6%; with 100% employer match about $210,563 at 4% or $140,375 at 6%. |
| Mark J. Sokolowski, MD Sc 401(K) Plan | - | 6 | $533,898 | $78,230 | $13,038iApproximate average salary by contribution assumption: employee only about $325,958 at 4% or $217,306 at 6%; with 50% employer match about $217,306 at 4% or $144,870 at 6%; with 100% employer match about $162,979 at 4% or $108,653 at 6%. |
| 2018 | 2 | 6 | $869,658 | $156,989 | $26,165iApproximate average salary by contribution assumption: employee only about $654,121 at 4% or $436,081 at 6%; with 50% employer match about $436,081 at 4% or $290,720 at 6%; with 100% employer match about $327,060 at 4% or $218,040 at 6%. |
| MARK J. SOKOLOWSKI, M.D., S.C. CASH BALANCE PLAN | - | 5 | $528,456 | $82,568 | $16,514iApproximate average salary by contribution assumption: employee only about $412,840 at 4% or $275,227 at 6%; with 50% employer match about $275,227 at 4% or $183,484 at 6%; with 100% employer match about $206,420 at 4% or $137,613 at 6%. |
| Mark J. Sokolowski, MD Sc 401(K) Plan | - | 6 | $341,202 | $74,421 | $12,404iApproximate average salary by contribution assumption: employee only about $310,088 at 4% or $206,725 at 6%; with 50% employer match about $206,725 at 4% or $137,817 at 6%; with 100% employer match about $155,044 at 4% or $103,363 at 6%. |
| 2017 | 2 | 7 | $772,604 | $138,532 | $19,790iApproximate average salary by contribution assumption: employee only about $494,757 at 4% or $329,838 at 6%; with 50% employer match about $329,838 at 4% or $219,892 at 6%; with 100% employer match about $247,379 at 4% or $164,919 at 6%. |
| MARK J. SOKOLOWSKI, M.D., S.C. CASH BALANCE PLAN | - | 5 | $485,259 | $80,339 | $16,068iApproximate average salary by contribution assumption: employee only about $401,695 at 4% or $267,797 at 6%; with 50% employer match about $267,797 at 4% or $178,531 at 6%; with 100% employer match about $200,848 at 4% or $133,898 at 6%. |
| Mark J. Sokolowski, MD Sc 401(K) Plan | - | 7 | $287,345 | $58,193 | $8,313iApproximate average salary by contribution assumption: employee only about $207,832 at 4% or $138,555 at 6%; with 50% employer match about $138,555 at 4% or $92,370 at 6%; with 100% employer match about $103,916 at 4% or $69,277 at 6%. |
| 2016 | 2 | 7 | $523,450 | $122,816 | $17,545iApproximate average salary by contribution assumption: employee only about $438,629 at 4% or $292,419 at 6%; with 50% employer match about $292,419 at 4% or $194,946 at 6%; with 100% employer match about $219,314 at 4% or $146,210 at 6%. |
| MARK J. SOKOLOWSKI, M.D., S.C. CASH BALANCE PLAN | - | 5 | $339,111 | $78,964 | $15,793iApproximate average salary by contribution assumption: employee only about $394,820 at 4% or $263,213 at 6%; with 50% employer match about $263,213 at 4% or $175,476 at 6%; with 100% employer match about $197,410 at 4% or $131,607 at 6%. |
| Mark J. Sokolowski, MD Sc 401(K) Plan | - | 7 | $184,339 | $43,852 | $6,265iApproximate average salary by contribution assumption: employee only about $156,614 at 4% or $104,410 at 6%; with 50% employer match about $104,410 at 4% or $69,606 at 6%; with 100% employer match about $78,307 at 4% or $52,205 at 6%. |
| 2015 | 2 | 6 | $359,199 | $145,111 | $24,185iApproximate average salary by contribution assumption: employee only about $604,629 at 4% or $403,086 at 6%; with 50% employer match about $403,086 at 4% or $268,724 at 6%; with 100% employer match about $302,315 at 4% or $201,543 at 6%. |
| MARK J. SOKOLOWSKI, M.D., S.C. CASH BALANCE PLAN | - | 2 | $237,101 | $89,397 | $44,699iApproximate average salary by contribution assumption: employee only about $1,117,463 at 4% or $744,975 at 6%; with 50% employer match about $744,975 at 4% or $496,650 at 6%; with 100% employer match about $558,731 at 4% or $372,488 at 6%. |
| Mark J. Sokolowski, MD Sc 401(K) Plan | - | 6 | $122,098 | $55,714 | $9,286iApproximate average salary by contribution assumption: employee only about $232,142 at 4% or $154,761 at 6%; with 50% employer match about $154,761 at 4% or $103,174 at 6%; with 100% employer match about $116,071 at 4% or $77,381 at 6%. |
| 2014 | 2 | 4 | $218,949 | $121,074 | $30,269iApproximate average salary by contribution assumption: employee only about $756,713 at 4% or $504,475 at 6%; with 50% employer match about $504,475 at 4% or $336,317 at 6%; with 100% employer match about $378,356 at 4% or $252,238 at 6%. |
| MARK J. SOKOLOWSKI, M.D., S.C. CASH BALANCE PLAN | - | 3 | $152,616 | $69,202 | $23,067iApproximate average salary by contribution assumption: employee only about $576,683 at 4% or $384,456 at 6%; with 50% employer match about $384,456 at 4% or $256,304 at 6%; with 100% employer match about $288,342 at 4% or $192,228 at 6%. |
| Mark J. Sokolowski, MD Sc 401(K) Plan | - | 4 | $66,333 | $51,872 | $12,968iApproximate average salary by contribution assumption: employee only about $324,200 at 4% or $216,133 at 6%; with 50% employer match about $216,133 at 4% or $144,089 at 6%; with 100% employer match about $162,100 at 4% or $108,067 at 6%. |
| 2013 | 2 | 4 | $79,940 | $95,174 | $23,794iApproximate average salary by contribution assumption: employee only about $594,838 at 4% or $396,558 at 6%; with 50% employer match about $396,558 at 4% or $264,372 at 6%; with 100% employer match about $297,419 at 4% or $198,279 at 6%. |
| MARK J. SOKOLOWSKI, M.D., S.C. CASH BALANCE PLAN | - | 4 | $73,974 | $73,974 | $18,494iApproximate average salary by contribution assumption: employee only about $462,338 at 4% or $308,225 at 6%; with 50% employer match about $308,225 at 4% or $205,483 at 6%; with 100% employer match about $231,169 at 4% or $154,113 at 6%. |
| Mark J. Sokolowski, MD Sc 401(K) Plan | - | 4 | $5,966 | $21,200 | $5,300iApproximate average salary by contribution assumption: employee only about $132,500 at 4% or $88,333 at 6%; with 50% employer match about $88,333 at 4% or $58,889 at 6%; with 100% employer match about $66,250 at 4% or $44,167 at 6%. |