Cisco Catalyst 3850 EOL

Cisco Catalyst 3850 EOL: Official Dates, Milestones, and Replacement Guide

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Last verified: 2026-11-14

As of November 2026, all Cisco Catalyst 3850 Series switches have passed End of Sale, and lifecycle support is split across two official bulletins depending on port media. Copper and multigigabit (mGig) Catalyst 3850 models reached their Last Date of Support on October 31, 2025 under bulletin EOL13188, meaning they are completely unsupported. Fiber (SFP/SFP+) Catalyst 3850 models remain supported under active contracts until April 30, 2027 under bulletin EOL13873, though their software vulnerability support has already ended.

Cisco Catalyst 3850 EOL

Quick Specs Context

Introduced in 2013, the Cisco Catalyst 3850 Series is a 1RU stackable enterprise access-layer switch family running Cisco IOS XE on the UADP 1.0 ASIC. It was Cisco’s first fixed-access platform to integrate a wireless LAN controller directly into the switch architecture alongside StackWise-480 data stacking and StackPower redundancy.

Specification Catalyst 3850 Series Baseline
Form Factor 1RU fixed-configuration with modular uplink slot
Downlink Ports 24 or 48 ports (1G RJ45, mGig, or 1G/10G SFP/SFP+)
Modular Uplinks Optional 4x1G, 2x10G, 4x10G, or 2x40G network modules
Switching Capacity 88 Gbps (24-port) to 176 Gbps (48-port 1G models)
Stacking Bandwidth 480 Gbps via StackWise-480 (except WS-C3850-48XS)
Memory / Storage 4 GB DRAM (8 GB on 48XS) / 2 GB Flash (4 GB on select SFP+ SKUs)
Last Supported OS Cisco IOS XE Gibraltar 16.12.x (16.12.14)

Cisco Catalyst 3850 EOL/EOS Timeline

Cisco split the Catalyst 3850 Series across two hardware bulletins (and a separate license bulletin, EOL14973). If your deployment mixes copper and fiber switches in a single StackWise-480 stack, the entire stack’s effective support eligibility is constrained by the earliest hardware milestone among its members.

Milestone Copper & mGig Models (EOL13188) Fiber SFP / SFP+ Models (EOL13873) Status (as of Nov 2026)
Affected Models WS-C3850-24T/P/U, 48T/P/U/F, 24XU, 12X48U WS-C3850-12S, 24S, 12XS, 16XS, 24XS, 32XS, 48XS —
EOL Announcement Date October 31, 2019 April 30, 2021 Past
End-of-Sale Date October 30, 2020 April 30, 2022 Past
Last Ship Date January 29, 2021 July 30, 2022 Past
End of SW Maintenance Releases October 30, 2021 April 30, 2023 Past
End of New Service Attachment October 30, 2021 April 30, 2023 Past
End of Vulnerability/Security Support October 31, 2025 (Amended) April 29, 2025 Past
End of Service Contract Renewal January 28, 2025 July 29, 2026 Past
Last Date of Support October 31, 2025 April 30, 2027 Copper: Past / Fiber: Active

Note: Cisco also issued bulletin EOL14973 for Catalyst 3850 DNA/software license SKUs, setting an End-of-Sale date of September 5, 2023, and Last Ship Date of December 4, 2023.

What Each Milestone Means in Practice

  • End-of-Sale Date (Passed): Cisco no longer sells new Catalyst 3850 switches through direct or partner channels; existing hardware continues operating normally without interruption.

  • End of SW Maintenance Releases (Passed): Cisco Engineering no longer develops new features or non-security bug fixes; the platform is permanently capped at Cisco IOS XE 16.12.x and cannot upgrade to IOS XE 17.x.

  • End of Vulnerability/Security Support (Passed): As of November 2026, neither copper nor fiber 3850 switches receive scheduled CVE patches or PSIRT security remedies, even with an active support contract.

  • End of Service Contract Renewal (Passed): You can no longer extend or renew Cisco Smart Net Total Care contracts on any Catalyst 3850 model.

  • Last Date of Support (Passed for Copper; April 30, 2027 for Fiber): After this date, Cisco TAC support, hardware RMA replacements, and software download entitlements terminate completely.

Replacement Options

Cisco’s official migration documentation and EOL bulletins designate the Cisco Catalyst 9300 Series as the direct Official replacement family for the Catalyst 3850 Series.

  • Standard 1G Copper Access (WS-C3850-24T/48T, 24P/48P, 24U/48U): Official replacement is the corresponding Catalyst 9300 SKU (C9300-24T/48T, C9300-24P/48P, C9300-24U/48U).

  • Multigigabit Copper (WS-C3850-24XU, WS-C3850-12X48U): Recommended migration family is the Catalyst 9300 mGig lineup (C9300-24UX, C9300-48UXM, or C9300X models).

  • Fiber Aggregation / Distribution (WS-C3850-12S/24S, 12XS/24XS/48XS): Recommended migration family is the Catalyst 9300 Fiber lineup (C9300-24S, C9300-48S, or C9300X-12Y/24Y for 10G/25G SFP28).

  • Budget-Constrained / Basic Layer 2-3 Branch Access: Similar / alternative product (PB Networks assessment) is the Cisco Catalyst 9200 / 9200L Series, which lowers acquisition cost for sites that do not need UPOE, StackPower, or full SD-Access scale.

Spec Comparison: Catalyst 3850 vs. Catalyst 9300

Comparing a standard 48-port PoE+ access model (WS-C3850-48P vs. C9300-48P) illustrates the architectural jump from UADP 1.0 to UADP 2.0:

Feature / Specification Cisco Catalyst 3850 (WS-C3850-48P) Cisco Catalyst 9300 (C9300-48P)
ASIC Architecture UADP 1.0 UADP 2.0 (UADP 2.0sec on 9300X)
CPU & Memory MIPS / 4 GB DRAM, 2 GB Flash Quad-core x86 / 8 GB DRAM, 16 GB Flash (16 GB DRAM on 9300X)
Max Stacking Bandwidth 480 Gbps (StackWise-480) 480 Gbps (StackWise-480) / 1 Tbps (StackWise-1T on 9300X)
Modular Uplink Options Up to 4x10G or 2x40G Up to 8x10G, 4x25G, 2x40G, or 2x100G (9300X)
Max PoE Standard IEEE 802.3at PoE+ (30W) / 60W Cisco UPOE IEEE 802.3bt UPOE+ (90W per port on UPOE+ SKUs)
Operating System IOS XE 16.12.x (capped) IOS XE 17.x+ (active development)
Licensing Model Perpetual LAN Base / IP Base / IP Services (PAK/RTU) Perpetual Network Essentials/Advantage + mandatory DNA/Networking Subscription

Migration Friction & Caveats

Moving from Catalyst 3850 to Catalyst 9300 is not a drop-in swap. Before ordering hardware, account for four specific compatibility constraints:

  1. No Mixed Stacking: You cannot mix Catalyst 3850 and Catalyst 9300 switches in the same StackWise-480 stack. New 9300 stacks must be built and cut over independently.

  2. Uplink Network Module Reuse: Per the Cisco Catalyst 9300 Data Sheet, legacy C3850-NM-* network modules (such as C3850-NM-4-10G and C3850-NM-2-40G) are supported in standard modular Catalyst 9300 chassis, but are not compatible with fixed-uplink C9300L or C9300X models.

  3. Power Supplies & StackPower: Catalyst 3850 and Catalyst 9300 share PWR-C1-* AC power supply form factors (PWR-C1-350WAC, 715WAC, 1100WAC), though Cisco’s upgrade documentation advises validating exact PSU revision and wattage requirements per target SKU rather than assuming universal transfer.

  4. Licensing & CLI Shift: The Catalyst 3850 used one-time perpetual feature tiers (-L LAN Base, -S IP Base, -E IP Services). Catalyst 9300 switches require Smart Licensing via Cisco Smart Software Manager (CSSM) and pair perpetual Network Essentials/Advantage tiers with a mandatory term-based Cisco DNA or Cisco Networking Subscription. Legacy IOS XE 16.x QoS and wireless controller commands also differ in IOS XE 17.x—Cisco removed the embedded wireless controller architecture used on the 3850.

Used-Equipment Notes

On the secondary market, Catalyst 3850 switches remain inexpensive and plentiful, making them common spares for extending existing stacks or building homelabs. When buying refurbished units, verify three items on the physical chassis label:

  • License Suffix (-L, -S, -E): Confirm whether the unit is LAN Base (-L), IP Base (-S), or IP Services (-E), as Cisco no longer sells Right-to-Use (RTU) upgrade licenses under EOL14973.

  • Airflow Direction on Fiber SKUs: High-density fiber models like the WS-C3850-48XS come in front-to-back (-S/-E) and back-to-front (-F-S/-F-E) airflow variants with color-coded fan and PSU latches. Mixing airflow directions in a single chassis causes thermal faults.

  • Included Uplink Module & PSU: Many used listings sell bare chassis without the C3850-NM-* uplink module or with a single 350W PSU that cannot power a full 48-port PoE+ load.

The PB Networks Verdict

If you are running copper or mGig Catalyst 3850 switches in production, you are already operating past Last Date of Support and should prioritize replacement—particularly for switches handling routed segments, guest access, or compliance-audited workloads, as zero CVE patches will ever be released. Fiber 3850 models have until April 30, 2027 for hardware RMA under existing contracts, giving you a short window to budget a staged cutover to the Catalyst 9300. Third-party maintenance (TPM) is a viable short-term stopgap for hardware sparing on stable internal Layer 2 access closets, but it cannot mitigate unpatched IOS XE security vulnerabilities.

FAQ

Are Cisco Catalyst 3850 switches completely end of life? Yes. Copper and multigigabit Catalyst 3850 switches passed their Last Date of Support on October 31, 2025, while fiber (SFP/SFP+) models remain under hardware support until April 30, 2027, for customers with active contracts.

Will my Cisco 3850 stop working after the Last Date of Support? No. Cisco does not remotely disable hardware at End of Support; the switch will continue forwarding traffic until a physical component fails, though you lose access to TAC support, RMAs, and security patches.

What is the official replacement for the Cisco Catalyst 3850? Cisco designates the Catalyst 9300 Series as the official replacement family, mapping 24- and 48-port data, PoE+, UPOE, mGig, and fiber 3850 models to equivalent Catalyst 9300 and 9300X switches.

Can I stack a Cisco 3850 with a Catalyst 9300? No. Catalyst 3850 and Catalyst 9300 switches cannot be combined in the same StackWise stack, even though standard Catalyst 9300 models also use StackWise-480 technology.

What is the last supported IOS XE version for the Cisco 3850?The Catalyst 3850 Series is capped at the Cisco IOS XE Gibraltar 16.12.x release train (ending at 16.12.14) and cannot be upgraded to IOS XE 17.x.

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