RANKING · 2020 CENSUS · 500 SHOWN OF 3,135

Highest Medicare coverage, US counties · 2020

US counties ranked by the share of people covered by Medicare, alone or in combination with other coverage (2020 ACS). A close proxy for retirement geography.

All statesAll rankings

SAME RANKING BYCities States Metros ZIP codes

RELATEDLargest foreign-born population Most residents with a disability Largest veteran population Most uninsured people Largest senior population Most unmarried people

RANKPLACESTATEPOPMEDICAREVS –

501Carter County, MTMT1,38326.4%–

502Banner County, NENE68626.4%–

503Hettinger County, NDND2,49226.4%–

504Trego County, KSKS2,74026.4%–

505Greenup County, KYKY35,21326.4%–

506Harlan County, KYKY24,72526.4%–

507Marinette County, WIWI42,57426.4%–

508Tallapoosa County, ALAL40,95326.3%–

509Carroll County, ARAR29,26326.3%–

510Clay County, WVWV7,53826.3%–

511Walthall County, MSMS13,92826.3%–

512Holt County, MOMO4,20026.3%–

513Ripley County, MOMO10,71726.3%–

514McCone County, MTMT1,72026.3%–

515Harlan County, NENE3,00026.3%–

516Lincoln County, NVNV4,32026.3%–

517Slope County, NDND62826.3%–

518Benewah County, IDID10,50826.3%–

519Gallatin County, ILIL4,61626.3%–

520Pulaski County, ILIL4,82026.3%–

521Pike County, KYKY54,72126.3%–

522Macon County, ALAL18,13226.2%–

523Marion County, ALAL29,09726.2%–

524Dade County, MOMO7,80426.2%–

525St. Lucie County, FLFL402,44926.2%–

526Murray County, MNMN7,94226.2%–

527Williamsburg County, SCSC29,66226.2%–

528Madison County, VAVA14,23726.2%–

529Pittsylvania County, VAVA59,49026.2%–

530Langlade County, WIWI19,53426.2%–

531Elbert County, GAGA20,07226.2%–

532Chautauqua County, KSKS3,32126.2%–

533Pawnee County, KSKS5,99126.2%–

534Russell County, KSKS6,58126.2%–

535Leslie County, KYKY9,62726.2%–

536Columbus County, NCNC50,48726.1%–

537Powell County, MTMT7,15726.1%–

538Jefferson County, NENE7,07026.1%–

539Campbell County, SDSD1,37726.1%–

540Henry County, TNTN32,89626.1%–

541Edwards County, TXTX1,37026.1%–

542Braxton County, WVWV11,88526.1%–

543Johnson County, WYWY8,90826.1%–

544Roberts County, TXTX86726.1%–

545Grays Harbor County, WAWA78,14426.1%–

546Franklin County, MEME30,82426.0%–

547Hancock County, MEME57,17126.0%–

548Winston County, MSMS17,47326.0%–

549Bollinger County, MOMO10,64626.0%–

550Maries County, MOMO8,39726.0%–

551Monroe County, MOMO8,95926.0%–

552Broadwater County, MTMT8,49326.0%–

553Beaufort County, NCNC44,67026.0%–

554Venango County, PAPA49,34626.0%–

555Union County, SCSC26,79926.0%–

556Goliad County, TXTX7,20826.0%–

557San Jacinto County, TXTX29,48826.0%–

558Marshall County, WVWV29,15926.0%–

559Ritchie County, WVWV8,03426.0%–

560Morgan County, WVWV18,02726.0%–

561Brevard County, FLFL663,98226.0%–

562Butte County, IDID2,78326.0%–

563Morris County, KSKS5,34826.0%–

564Republic County, KSKS4,64026.0%–

565Hardin County, TNTN27,98326.0%–

566Asotin County, WAWA22,54526.0%–

567Klickitat County, WAWA24,33126.0%–

568Winston County, ALAL23,82925.9%–

569Wayne County, KYKY19,59725.9%–

570Berkshire County, MAMA128,22425.9%–

571Charlevoix County, MIMI26,03625.9%–

572Big Stone County, MNMN5,05425.9%–

573Craig County, OKOK14,51825.9%–

574Day County, SDSD5,48425.9%–

575Campbell County, TNTN40,29025.9%–

576Leon County, TXTX16,89425.9%–

577James City County, VAVA83,32625.9%–

578Brooke County, WVWV21,14225.9%–

579Doddridge County, WVWV7,63425.9%–

580Dooly County, GAGA11,15625.9%–

581Monona County, IAIA8,53925.9%–

582Wilson County, KSKS8,29925.9%–

583Knott County, KYKY13,32125.9%–

584Martin County, NCNC21,60125.8%–

585Blackford County, ININ11,73025.8%–

586Itasca County, MNMN45,40425.8%–

587Powder River County, MTMT1,78125.8%–

588Hitchcock County, NENE2,46725.8%–

589San Miguel County, NMNM26,26025.8%–

590Bennington County, VTVT36,63025.8%–

591Raleigh County, WVWV71,77525.8%–

592Platte County, WYWY8,63425.8%–

593Roane County, TNTN57,39525.8%–

594Rush County, KSKS2,84525.8%–

595Grayson County, KYKY27,40625.8%–

596Menifee County, KYKY6,43025.8%–

597Hawkins County, TNTN59,55925.8%–

598Dallas County, MOMO18,02525.7%–

599Dukes County, MAMA21,21925.7%–

600Madison County, NCNC22,55325.7%–

601Monroe County, OHOH12,99425.7%–

602Hood County, TXTX70,50125.7%–

603Crawford County, WIWI15,91025.7%–

604Montrose County, COCO44,59125.7%–

605Appanoose County, IAIA12,07725.7%–

606Gove County, KSKS2,63125.7%–

607Letcher County, KYKY19,95225.7%–

608Oxford County, MEME60,34625.7%–

609Susquehanna County, PAPA38,23725.7%–

610Lamar County, ALAL13,58725.6%–

611Franklin County, ARAR17,72525.6%–

612Forest County, WIWI9,57425.6%–

613Tensas Parish, LALA3,70025.6%–

614Kemper County, MSMS8,60025.6%–

615Gasconade County, MOMO14,78425.6%–

616Daniels County, MTMT1,61225.6%–

617Frontier County, NENE2,65525.6%–

618Valley County, NENE4,09425.6%–

619Santa Fe County, NMNM156,90725.6%–

620Clatsop County, OROR40,92625.6%–

621Harney County, OROR7,38025.6%–

622Bamberg County, SCSC12,79625.6%–

623Cocke County, TNTN37,88925.6%–

624Charlotte County, VAVA11,40125.6%–

625Wayne County, WVWV37,30925.6%–

626Calhoun County, ILIL4,30025.6%–

627Saguache County, COCO6,73225.6%–

628Marshall County, KYKY31,65925.6%–

629Barbour County, ALAL24,60725.5%–

630Boyd County, KYKY47,75125.5%–

631Randolph County, ARAR18,87625.5%–

632Sullivan County, TNTN163,75925.5%–

633Inyo County, CACA18,15825.5%–

634Park County, COCO18,31425.5%–

635Warren County, GAGA5,26925.5%–

636Martin County, MNMN19,44025.5%–

637Hidalgo County, NMNM3,92925.5%–

638Bedford County, PAPA47,48025.5%–

639Cambria County, PAPA128,96825.5%–

640Hand County, SDSD3,12125.5%–

641Windsor County, VTVT57,31225.5%–

642Hardy County, WVWV14,33725.5%–

643White County, GAGA29,80225.5%–

644Lincoln County, COCO5,64525.5%–

645Carroll County, MOMO8,41725.4%–

646Prairie County, ARAR7,92325.4%–

647Jackson Parish, LALA15,83425.4%–

648Tishomingo County, MSMS18,63925.4%–

649Furnas County, NENE4,52425.4%–

650Grant County, NENE56125.4%–

651Thayer County, NENE4,84225.4%–

652Rutherford County, NCNC65,74525.4%–

653Lee County, SCSC15,73025.4%–

654Blanco County, TXTX13,58125.4%–

655Stewart County, GAGA4,63125.4%–

656Hancock County, ILIL16,80325.4%–

657Audubon County, IAIA5,50925.4%–

658Green County, KYKY11,64425.4%–

659Russell County, KYKY18,60825.4%–

660Waldo County, MEME40,69325.4%–

661Burt County, NENE6,67825.4%–

662Yates County, NYNY24,54725.4%–

663McDowell County, NCNC45,19825.4%–

664Monroe County, ALAL18,96525.3%–

665Cochise County, AZAZ126,33225.3%–

666Ashley County, ARAR17,83125.3%–

667Wolfe County, KYKY6,29825.3%–

668Guadalupe County, NMNM4,34325.3%–

669Wilkes County, NCNC66,23325.3%–

670Klamath County, OROR70,27425.3%–

671Elk County, PAPA29,92625.3%–

672Warren County, PAPA37,03825.3%–

673Carter County, TNTN57,36125.3%–

674Bosque County, TXTX18,91825.3%–

675Botetourt County, VAVA34,14425.3%–

676Greensville County, VAVA11,18125.3%–

677Wythe County, VAVA27,98325.3%–

678Bell County, KYKY22,82925.3%–

679DeSoto County, FLFL37,07825.3%–

680Calhoun County, ARAR4,63225.2%–

681Monroe County, ARAR6,24425.2%–

682Perry County, ARAR10,30925.2%–

683Towner County, NDND2,04025.2%–

684Latimer County, OKOK9,64525.2%–

685Gregory County, SDSD4,03725.2%–

686Claiborne County, TNTN33,22925.2%–

687Fayette County, TXTX25,45925.2%–

688Rutland County, VTVT59,65325.2%–

689Accomack County, VAVA33,85925.2%–

690Wilkinson County, GAGA8,65025.2%–

691Mason County, ILIL12,41125.2%–

692Kossuth County, IAIA14,32225.2%–

693Owsley County, KYKY3,93225.2%–

694Grainger County, TNTN25,73925.2%–

695Jackson County, ARAR16,74125.1%–

696Surry County, VAVA6,60325.1%–

697Grant County, MNMN6,08525.1%–

698Henry County, MOMO22,67125.1%–

699Fergus County, MTMT11,82525.1%–

700Knox County, NENE8,33525.1%–

701Columbia County, NYNY60,16825.1%–

702Greene County, NYNY47,23825.1%–

703Ellis County, OKOK3,61325.1%–

704Perkins County, SDSD2,85325.1%–

705Sully County, SDSD1,47925.1%–

706Comanche County, TXTX14,43225.1%–

707Windham County, VTVT45,20425.1%–

708Crawford County, MOMO22,92925.1%–

709Taylor County, GAGA7,81825.1%–

710Gem County, IDID21,77325.1%–

711Page County, IAIA14,85625.1%–

712Phillips County, KSKS4,72825.1%–

713Casey County, KYKY16,20525.1%–

714Somerset County, MEME51,62025.1%–

715Warren County, NYNY65,02025.1%–

716Clay County, ALAL14,20725.0%–

717Yalobusha County, MSMS12,37525.0%–

718Chatham County, NCNC85,11125.0%–

719Marshall County, OKOK16,25525.0%–

720Huntingdon County, PAPA43,00125.0%–

721Somerset County, PAPA72,00425.0%–

722Henderson County, TXTX88,59525.0%–

723Wirt County, WVWV4,87925.0%–

724Breathitt County, KYKY12,55825.0%–

725Golden Valley County, NDND1,80825.0%–

726Richardson County, NENE7,53025.0%–

727Hale County, ALAL15,19425.0%–

728Clayton County, IAIA16,84525.0%–

729Lincoln County, KSKS2,86125.0%–

730Washington County, KSKS5,53325.0%–

731Clinton County, KYKY9,13925.0%–

732Garrett County, MDMD28,37025.0%–

733Halifax County, NCNC46,53425.0%–

734Hertford County, NCNC19,01525.0%–

735Perkins County, NENE2,84924.9%–

736Osceola County, MIMI23,51624.9%–

737Sanilac County, MIMI40,08324.9%–

738Monroe County, MSMS33,31824.9%–

739Dent County, MOMO14,58424.9%–

740Macon County, MOMO15,19024.9%–

741Wright County, MOMO19,67124.9%–

742Adams County, NDND2,27524.9%–

743Pike County, PAPA62,80824.9%–

744Clay County, TXTX10,76424.9%–

745Judith Basin County, MTMT2,16224.9%–

746Pasco County, FLFL674,51624.9%–

747Crawford County, GAGA12,20624.9%–

748Boundary County, IDID13,99724.9%–

749Harper County, KSKS5,37024.9%–

750Lee County, KYKY7,29724.9%–

751Morgan County, KYKY14,41524.9%–

752Muhlenberg County, KYKY30,63424.9%–

753Lowndes County, ALAL9,35924.8%–

754Washington County, ALAL14,82224.8%–

755Bracken County, KYKY8,51124.8%–

756Traverse County, MNMN3,13024.8%–

757Quitman County, MSMS5,36424.8%–

758Garfield County, NENE1,71024.8%–

759Fulton County, NYNY52,21624.8%–

760LaMoure County, NDND4,13524.8%–

761Morgan County, OHOH13,62624.8%–

762McNairy County, TNTN26,23624.8%–

763Morgan County, TNTN22,16024.8%–

764Polk County, TNTN18,59224.8%–

765McCulloch County, TXTX7,47224.8%–

766Orleans County, VTVT27,60024.8%–

767Hancock County, WVWV27,72924.8%–

768Edgar County, ILIL16,32324.8%–

769Calhoun County, IAIA9,56224.8%–

770Ballard County, KYKY7,59424.8%–

771Stillwater County, MTMT9,44524.8%–

772Geneva County, ALAL27,55424.7%–

773Jackson County, ALAL54,28124.7%–

774Boone County, ARAR38,62824.7%–

775Ouachita County, ARAR21,73124.7%–

776Pope County, MNMN11,42024.7%–

777Sheridan County, MTMT3,43624.7%–

778Wibaux County, MTMT88524.7%–

779Burke County, NCNC88,65524.7%–

780Mercer County, PAPA107,86024.7%–

781Marion County, SCSC28,24224.7%–

782Caledonia County, VTVT30,41424.7%–

783Buckingham County, VAVA17,13724.7%–

784Essex County, VAVA10,65424.7%–

785Page County, VAVA23,76224.7%–

786Wood County, WVWV82,38524.7%–

787Richland County, WIWI17,03624.7%–

788Osborne County, KSKS3,28524.7%–

789Bristol, VAVA16,41824.7%–

790Dodge County, GAGA19,66324.7%–

791Laurens County, GAGA51,04124.7%–

792Brown County, ININ15,77724.7%–

793Cherokee County, IAIA11,36924.7%–

794Linn County, KSKS9,95024.7%–

795Abbeville County, SCSC24,83624.7%–

796Dickinson County, MIMI25,82724.6%–

797Otsego County, MIMI26,08024.6%–

798Otter Tail County, MNMN61,04124.6%–

799Barton County, MOMO11,79524.6%–

800Deuel County, NENE1,86224.6%–

801Fillmore County, NENE5,45824.6%–

802Keya Paha County, NENE79224.6%–

803Lyon County, NVNV65,08824.6%–

804Clearfield County, PAPA78,10024.6%–

805Marlboro County, SCSC25,48824.6%–

806Walworth County, SDSD5,21724.6%–

807Pickens County, GAGA37,16724.6%–

808Montezuma County, COCO26,67824.6%–

809Holmes County, FLFL20,11924.6%–

810Palm Beach County, FLFL1,575,72624.6%–

811Hamilton County, ILIL7,85924.6%–

812Putnam County, ILIL5,61924.6%–

813Schuyler County, ILIL6,65724.6%–

814Stephenson County, ILIL43,22024.6%–

815Van Buren County, IAIA7,13124.6%–

816Rooks County, KSKS4,64624.6%–

817Colbert County, ALAL59,47424.5%–

818Madison County, ARAR18,41024.5%–

819Calhoun County, MSMS12,64324.5%–

820Stoddard County, MOMO28,28424.5%–

821Taney County, MOMO57,00124.5%–

822Lake County, MTMT33,39224.5%–

823McLean County, NDND9,74024.5%–

824Cimarron County, OKOK2,05924.5%–

825Danville, VAVA41,64724.5%–

826Jackson County, WVWV27,45024.5%–

827East Carroll Parish, LALA6,76024.5%–

828Barber County, KSKS4,08324.5%–

829Perry County, ILIL20,16024.5%–

830Cass County, IAIA12,96024.5%–

831Mitchell County, KSKS5,59024.5%–

832McCreary County, KYKY17,12424.5%–

833Tioga County, PAPA40,50224.5%–

834Westmoreland County, PAPA349,32424.5%–

835Okanogan County, WAWA45,23024.5%–

836Covington County, ALAL37,94724.4%–

837Chicot County, ARAR9,10724.4%–

838Missaukee County, MIMI15,27424.4%–

839Tuscola County, MIMI52,68024.4%–

840Crow Wing County, MNMN69,13224.4%–

841Ralls County, MOMO10,44424.4%–

842Phillips County, MTMT4,20324.4%–

843Antelope County, NENE6,35224.4%–

844Torrance County, NMNM16,10024.4%–

845Schoharie County, NYNY30,17624.4%–

846Schuyler County, NYNY16,92424.4%–

847Atoka County, OKOK14,60924.4%–

848Calhoun County, SCSC14,18824.4%–

849Marion County, TNTN29,80424.4%–

850Hall County, TXTX2,73724.4%–

851Jasper County, TXTX33,07524.4%–

852Kane County, UTUT8,59724.4%–

853Kanawha County, WVWV172,38124.4%–

854Ohio County, WVWV40,49624.4%–

855Pointe Coupee Parish, LALA19,52024.4%–

856Hot Spring County, ARAR33,45124.4%–

857Nassau County, FLFL106,87924.4%–

858Suwannee County, FLFL48,14924.4%–

859Marshall County, ILIL11,47324.4%–

860Shelby County, IAIA11,68924.4%–

861Wright County, IAIA12,80124.4%–

862Valley County, MTMT7,38524.4%–

863Fayette County, PAPA123,02124.4%–

864Lewis County, WAWA88,06224.4%–

865Juneau County, WIWI26,64924.4%–

866Walker County, ALAL65,14024.3%–

867Lawrence County, ARAR16,27324.3%–

868Lincoln County, ARAR12,76424.3%–

869Scott County, TNTN22,67124.3%–

870Franklin County, MAMA70,69824.3%–

871Itawamba County, MSMS24,15224.3%–

872Smith County, MSMS13,99124.3%–

873Barry County, MOMO36,20024.3%–

874Pembina County, NDND6,56824.3%–

875Fulton County, PAPA14,48324.3%–

876Jones County, TXTX20,86124.3%–

877Kenedy County, TXTX31924.3%–

878Newton County, TXTX11,95424.3%–

879Goochland County, VAVA29,18724.3%–

880Randolph County, GAGA6,15624.3%–

881Burnet County, TXTX57,01524.3%–

882Lawrence County, PAPA83,91124.3%–

883Marion County, GAGA7,67624.3%–

884Norton County, KSKS5,28824.3%–

885Livingston County, KYKY8,86324.3%–

886Goshen County, WYWY12,64024.3%–

887Breckinridge County, KYKY21,50324.2%–

888Kittson County, MNMN4,03124.2%–

889Franklin County, MSMS7,49124.2%–

890Butler County, MOMO41,90424.2%–

891Hooker County, NENE68624.2%–

892Gates County, NCNC10,23424.2%–

893Bottineau County, NDND6,28424.2%–

894Armstrong County, PAPA63,69824.2%–

895Bon Homme County, SDSD7,24424.2%–

896Live Oak County, TXTX11,92924.2%–

897Barron County, WIWI46,48424.2%–

898Pepin County, WIWI7,51324.2%–

899Grundy County, MOMO9,74424.2%–

900Greene County, IAIA8,65824.2%–

901Gilchrist County, FLFL20,48824.2%–

902Dade County, GAGA16,15424.2%–

903Chase County, KSKS2,57224.2%–

904Ellsworth County, KSKS6,25724.2%–

905Johnson County, KYKY22,05124.2%–

906Chase County, NENE3,71824.2%–

907Buffalo County, WIWI13,31824.2%–

908Green Lake County, WIWI19,30524.2%–

909Butler County, ALAL18,10024.1%–

910Talladega County, ALAL81,60324.1%–

911Emmet County, MIMI33,77524.1%–

912Cottonwood County, MNMN11,40524.1%–

913Douglas County, MNMN40,12024.1%–

914Lake of the Woods County, MNMN3,77024.1%–

915Luna County, NMNM25,40724.1%–

916Rockingham County, NCNC94,19524.1%–

917Surry County, NCNC72,28724.1%–

918Newport County, RIRI83,05124.1%–

919Jefferson County, TNTN60,02424.1%–

920Lake County, TNTN6,24924.1%–

921Perry County, TNTN9,12624.1%–

922Delta County, TXTX5,54924.1%–

923Sequatchie County, TNTN17,86124.1%–

924White County, ILIL13,25024.1%–

925Sac County, IAIA9,52524.1%–

926Carlisle County, KYKY4,74724.1%–

927Lenoir County, NCNC55,83724.1%–

928Kalkaska County, MIMI18,69324.0%–

929Knox County, MOMO3,72824.0%–

930Coal County, OKOK5,43624.0%–

931Haskell County, OKOK11,78724.0%–

932Crawford County, PAPA81,79224.0%–

933McMinn County, TNTN57,40424.0%–

934White County, TNTN29,61224.0%–

935Shenandoah County, VAVA45,83924.0%–

936Lincoln County, WVWV19,17724.0%–

937Clarke County, ALAL22,01424.0%–

938Meriwether County, GAGA21,51624.0%–

939Wayne County, ILIL15,88224.0%–

940Ness County, KSKS2,61724.0%–

941Preston County, WVWV34,00424.0%–

942Randolph County, ALAL23,16323.9%–

943Logan County, ARAR21,63323.9%–

944Shasta County, CACA181,64823.9%–

945DeKalb County, MOMO9,79523.9%–

946Mississippi County, MOMO12,00323.9%–

947Pierce County, NDND3,83823.9%–

948Sargent County, NDND3,71123.9%–

949Harrison County, OHOH14,07023.9%–

950Northumberland County, PAPA89,92023.9%–

951Houston County, TNTN8,47923.9%–

952Brooks County, TXTX6,57923.9%–

953Cass County, TXTX28,65123.9%–

954Morris County, TXTX12,13323.9%–

955Augusta County, VAVA78,94023.9%–

956Bedford County, VAVA83,05923.9%–

957Floyd County, VAVA15,78923.9%–

958Lincoln County, WIWI28,40323.9%–

959Jefferson County, OHOH63,59723.9%–

960Beaverhead County, MTMT10,04323.9%–

961Taylor County, WVWV16,28723.9%–

962Ocean County, NJNJ673,74623.9%–

963Ohio County, ININ5,99423.9%–

964Ringgold County, IAIA4,64223.9%–

965Kiowa County, KSKS2,43223.9%–

966Wallace County, KSKS1,44123.9%–

967Crittenden County, KYKY8,80723.9%–

968Lawrence County, KYKY15,76523.9%–

969Dorchester County, MDMD33,62823.9%–

970Hancock County, MSMS46,87323.8%–

971Perry County, MSMS11,57723.8%–

972Custer County, NENE10,50023.8%–

973Johnson County, NENE5,21823.8%–

974Sullivan County, NHNH43,96123.8%–

975Jackson County, OROR221,79523.8%–

976Sherman County, OROR2,05123.8%–

977Beaver County, PAPA166,03223.8%–

978Stanley County, SDSD3,01823.8%–

979Obion County, TNTN30,06723.8%–

980Washington County, NYNY59,35323.8%–

981Washington County, FLFL26,69523.8%–

982Adams County, IAIA3,61723.8%–

983Marion County, KSKS11,63423.8%–

984Clay County, KYKY19,46523.8%–

985Magoffin County, KYKY11,11023.8%–

986Sagadahoc County, MEME37,97923.8%–

987West Carroll Parish, LALA9,15623.7%–

988Oceana County, MIMI27,17723.7%–

989Lincoln County, MNMN5,58323.7%–

990Pine County, MNMN30,47223.7%–

991Alcorn County, MSMS34,56923.7%–

992Caldwell County, NCNC81,10523.7%–

993Montgomery County, NCNC26,40323.7%–

994Choctaw County, OKOK14,05923.7%–

995Jefferson County, OKOK5,43123.7%–

996Love County, OKOK10,78023.7%–

997Lawrence County, SDSD29,45923.7%–

998Mason County, WVWV24,70723.7%–

999Lafayette County, MOMO33,53123.7%–

1000Park County, WYWY31,17123.7%–

SHOWING 501–1,000 OF 3,135

Download CSV (full list, 3,135 rows)

UPDATED 2026-08-08 · DATA: US CENSUS BUREAU DECENNIAL CENSUS