R50.9
Billable

Fever, unspecified

Billable / Specific Code

What is Fever, unspecified?

ICD-10-CM R50.9 is the diagnosis code for Fever, unspecified. This code falls under the section "General symptoms and signs" within Chapter 18 — Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R99). It is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes. Medical coders and healthcare providers use this code to document and classify diagnoses in electronic health records, insurance claims, and clinical databases.

💡 Inclusions

Coding Guidelines for R50.9

✅ This Code Includes

  • Fever NOS
  • Fever of unknown origin [FUO]
  • Fever with chills
  • Fever with rigors
  • Hyperpyrexia NOS
  • Persistent fever
  • Pyrexia NOS

ICD-10-CM Code Hierarchy

Understanding where R50.9 sits in the ICD-10-CM classification helps ensure proper coding:

Current CodeR50.9 — Fever, unspecified
Sub-Codes (1918)
A00A01A02A03A04A05A06A07A08A09A15A17A18A19A20A21A22A23A24A25A26A27A28A30A31A32A33A34A35A36A37A38A39A40A41A42A43A44A46A48A49A50A51A52A53A54A55A56A57A58A59A60A63A64A65A66A67A68A69A70A71A74A75A77A78A79A80A81A82A83A84A85A86A87A88A89A90A91A92A93A94A95A96A98A99B00B01B02B03B04B05B06B07B08B09B10B15B16B17B18B19B20B25B26B27B30B33B34B35B36B37B38B39B40B41B42B43B44B45B46B47B48B49B50B51B52B53B54B55B56B57B58B59B60B64B65B66B67B68B69B70B71B72B73B74B75B76B77B78B79B80B81B82B83B85B86B87B88B89B90B91B92B94B95B96B97B99C00C01C02C03C04C05C06C07C08C09C10C11C12C13C14C15C16C17C18C19C20C21C22C23C24C25C26C30C31C32C33C34C37C38C39C40C41C43C44C45C46C47C48C49C4AC50C51C52C53C54C55C56C57C58C60C61C62C63C64C65C66C67C68C69C70C71C72C73C74C75C76C77C78C79C7AC7BC80C81C82C83C84C85C86C88C90C91C92C93C94C95C96D00D01D02D03D04D05D06D07D09D10D11D12D13D14D15D16D17D18D19D20D21D22D23D24D25D26D27D28D29D30D31D32D33D34D35D36D37D38D39D3AD40D41D42D43D44D45D46D47D48D49D50D51D52D53D55D56D57D58D59D60D61D62D63D64D65D66D67D68D69D70D71D72D73D74D75D76D77D78D80D81D82D83D84D86D89E00E01E02E03E04E05E06E07E08E09E10E11E13E15E16E20E21E22E23E24E25E26E27E28E29E30E31E32E34E35E36E40E41E42E43E44E45E46E50E51E52E53E54E55E56E58E59E60E61E63E64E65E66E67E68E70E71E72E73E74E75E76E77E78E79E80E83E84E85E86E87E88E89F01F02F03F04F05F06F07F09F10F11F12F13F14F15F16F17F18F19F20F21F22F23F24F25F28F29F30F31F32F33F34F39F40F41F42F43F44F45F48F50F51F52F53F54F55F59F60F63F64F65F66F68F69F70F71F72F73F78F79F80F81F82F84F88F89F90F91F93F94F95F98F99G00G01G02G03G04G05G06G07G08G09G10G11G12G13G14G20G21G23G24G25G26G30G31G32G35G36G37G40G43G44G45G46G47G50G51G52G53G54G55G56G57G58G59G60G61G62G63G64G65G70G71G72G73G80G81G82G83G89G90G91G92G93G94G95G96G97G98G99H00H01H02H04H05H10H11H15H16H17H18H20H21H22H25H26H27H28H30H31H32H33H34H35H36H40H42H43H44H46H47H49H50H51H52H53H54H55H57H59H60H61H62H65H66H67H68H69H70H71H72H73H74H75H80H81H82H83H90H91H92H93H94H95I00I01I02I05I06I07I08I09I10I11I12I13I15I16I1AI20I21I22I23I24I25I26I27I28I30I31I32I33I34I35I36I37I38I39I40I41I42I43I44I45I46I47I48I49I50I51I52I5AI60I61I62I63I65I66I67I68I69I70I71I72I73I74I75I76I77I78I79I80I81I82I83I85I86I87I88I89I95I96I97I99J00J01J02J03J04J05J06J09J10J11J12J13J14J15J16J17J18J20J21J22J30J31J32J33J34J35J36J37J38J39J40J41J42J43J44J45J47J4AJ60J61J62J63J64J65J66J67J68J69J70J80J81J82J84J85J86J90J91J92J93J94J95J96J98J99K00K01K02K03K04K05K06K08K09K11K12K13K14K20K21K22K23K25K26K27K28K29K30K31K35K36K37K38K40K41K42K43K44K45K46K50K51K52K55K56K57K58K59K60K61K62K63K64K65K66K67K68K70K71K72K73K74K75K76K77K80K81K82K83K85K86K87K90K91K92K94K95L00L01L02L03L04L05L08L10L11L12L13L14L20L21L22L23L24L25L26L27L28L29L30L40L41L42L43L44L45L49L50L51L52L53L54L55L56L57L58L59L60L62L63L64L65L66L67L68L70L71L72L73L74L75L76L80L81L82L83L84L85L86L87L88L89L90L91L92L93L94L95L97L98L99M00M01M02M04M05M06M07M08M10M11M12M13M14M15M16M17M18M19M1AM20M21M22M23M24M25M26M27M30M31M32M33M34M35M36M40M41M42M43M45M46M47M48M49M50M51M53M54M60M61M62M63M65M66M67M70M71M72M75M76M77M79M80M81M83M84M85M86M87M88M89M90M91M92M93M94M95M96M97M99N00N01N02N03N04N05N06N07N08N10N11N12N13N14N15N16N17N18N19N20N21N22N23N25N26N27N28N29N30N31N32N33N34N35N36N37N39N40N41N42N43N44N45N46N47N48N49N50N51N52N53N60N61N62N63N64N65N70N71N72N73N74N75N76N77N80N81N82N83N84N85N86N87N88N89N90N91N92N93N94N95N96N97N98N99O00O01O02O03O04O07O08O09O10O11O12O13O14O15O16O20O21O22O23O24O25O26O28O29O30O31O32O33O34O35O36O40O41O42O43O44O45O46O47O48O60O61O62O63O64O65O66O67O68O69O70O71O72O73O74O75O76O77O80O82O85O86O87O88O89O90O91O92O94O98O99O9AP00P01P02P03P04P05P07P08P09P10P11P12P13P14P15P19P22P23P24P25P26P27P28P29P35P36P37P38P39P50P51P52P53P54P55P56P57P58P59P60P61P70P71P72P74P76P77P78P80P81P83P84P90P91P92P93P94P95P96Q00Q01Q02Q03Q04Q05Q06Q07Q10Q11Q12Q13Q14Q15Q16Q17Q18Q20Q21Q22Q23Q24Q25Q26Q27Q28Q30Q31Q32Q33Q34Q35Q36Q37Q38Q39Q40Q41Q42Q43Q44Q45Q50Q51Q52Q53Q54Q55Q56Q60Q61Q62Q63Q64Q65Q66Q67Q68Q69Q70Q71Q72Q73Q74Q75Q76Q77Q78Q79Q80Q81Q82Q83Q84Q85Q86Q87Q89Q90Q91Q92Q93Q95Q96Q97Q98Q99QA0R00R01R03R04R05R06R07R09R10R11R12R13R14R15R16R17R18R19R20R21R22R23R25R26R27R29R30R31R32R33R34R35R36R37R39R40R41R42R43R44R45R46R47R48R49R50R51R52R53R54R55R56R57R58R59R60R61R62R63R64R65R68R69R70R71R73R74R75R76R77R78R79R80R81R82R83R84R85R86R87R88R89R90R91R92R93R94R97R99S00S01S02S03S04S05S06S07S08S09S10S11S12S13S14S15S16S17S19S20S21S22S23S24S25S26S27S28S29S30S31S32S33S34S35S36S37S38S39S40S41S42S43S44S45S46S47S48S49S50S51S52S53S54S55S56S57S58S59S60S61S62S63S64S65S66S67S68S69S70S71S72S73S74S75S76S77S78S79S80S81S82S83S84S85S86S87S88S89S90S91S92S93S94S95S96S97S98S99T07T14T15T16T17T18T19T20T21T22T23T24T25T26T27T28T30T31T32T33T34T36T37T38T39T40T41T42T43T44T45T46T47T48T49T50T51T52T53T54T55T56T57T58T59T60T61T62T63T64T65T66T67T68T69T70T71T73T74T75T76T78T79T80T81T82T83T84T85T86T87T88U07U09V00V01V02V03V04V05V06V09V10V11V12V13V14V15V16V17V18V19V20V21V22V23V24V25V26V27V28V29V30V31V32V33V34V35V36V37V38V39V40V41V42V43V44V45V46V47V48V49V50V51V52V53V54V55V56V57V58V59V60V61V62V63V64V65V66V67V68V69V70V71V72V73V74V75V76V77V78V79V80V81V82V83V84V85V86V87V88V89V90V91V92V93V94V95V96V97V98V99W00W01W03W04W05W06W07W08W09W10W11W12W13W1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Related Codes

Frequently Asked Questions

Is R50.9 a billable ICD-10-CM code?

Yes, R50.9 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.

What does R50.9 mean?

R50.9 is the ICD-10-CM diagnosis code for "Fever, unspecified". It is used by healthcare providers to classify and document this condition in medical records and insurance claims.

What is the parent code of R50.9?

The parent code of R50.9 is R50 ("Fever of other and unknown origin"). R50.9 provides a more specific classification within this category.

What section is R50.9 in?

R50.9 is located in Section R50-R69 — "General symptoms and signs" within Chapter 18 of the ICD-10-CM Tabular List.

What are the sub-codes of R50.9?

R50.9 has 1918 sub-code(s) that provide more specific detail: A00, A01, A02, A03, A04 and more.

When should I use R50.9?

Use R50.9 when the patients documented diagnosis matches "Fever, unspecified" and the clinical documentation supports this level of specificity. Always verify with the latest ICD-10-CM guidelines and payer requirements.

People Also Ask

What is the ICD-10 code for Fever, unspecified?

The ICD-10-CM code for Fever, unspecified is R50.9.

Can R50.9 be used for primary diagnosis?

Yes, R50.9 can be used as a primary diagnosis code since it is billable and specific.

What chapter is R50.9 in?

R50.9 is in Chapter 18 of the ICD-10-CM Tabular List.

Is R50.9 valid for 2026?

Yes, R50.9 is a valid ICD-10-CM code for the 2026 fiscal year, subject to official CMS updates.

See Also

← PreviousR50.84Febrile nonhemolytic transfusion reactionNext →R51Headache
Code Details
R50.9
Fever, unspecified
Billable / Specific Code
18 — Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R99)
R50-R69 — General symptoms and signs
2026 ICD-10-CM