diff --git a/.github/workflows/Check.yml b/.github/workflows/Check.yml
index df6ebcf..df4123c 100644
--- a/.github/workflows/Check.yml
+++ b/.github/workflows/Check.yml
@@ -33,19 +33,20 @@ jobs:
           ])
           Pkg.add([
               PackageSpec(name = "ExplicitImports", version = "1.9"),
-              PackageSpec(name = "PartitionedArrays", version = "0.5"),
+              PackageSpec(name = "PartitionedArrays"),
+              PackageSpec(name = "SparseMatricesCSR"),
           ])
       - name: ExplicitImports.jl code checks
         shell: julia --project=@explicit-imports {0}
         run: |
-          using HYPRE, ExplicitImports, PartitionedArrays
+          using HYPRE, ExplicitImports, PartitionedArrays, SparseMatricesCSR
           # Check HYPRE
           check_no_implicit_imports(HYPRE)
           check_no_stale_explicit_imports(HYPRE)
           check_all_qualified_accesses_via_owners(HYPRE)
           check_no_self_qualified_accesses(HYPRE)
           # Check extension modules
-          for ext in (:HYPREPartitionedArrays,)
+          for ext in (:HYPREPartitionedArrays, :HYPRESparseMatricesCSR)
               extmod = Base.get_extension(HYPRE, ext)
               if extmod !== nothing
                   check_no_implicit_imports(extmod)
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 43b4e39..ed9a4b2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,9 +9,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
  - PartitionedArrays.jl dependency upgraded from release series 0.3.x to release series
    0.5.x. ([#17], [#18])
- - PartitionedArrays.jl support is now moved to a package extension. ([#23])
  - CEnum.jl dependency upgraded to release series 0.5.x (release series 0.4.x still
    allowed). ([#17], [#18])
+ - PartitionedArrays.jl support is now moved to a package extension. ([#23])
+ - SparseMatricesCSR.jl support is now moved to a package extension. ([#24])
 
 ## [v1.5.0] - 2023-05-26
 ### Changed
diff --git a/Project.toml b/Project.toml
index b7be1e5..629dc3b 100644
--- a/Project.toml
+++ b/Project.toml
@@ -13,9 +13,11 @@ SparseMatricesCSR = "a0a7dd2c-ebf4-11e9-1f05-cf50bc540ca1"
 
 [weakdeps]
 PartitionedArrays = "5a9dfac6-5c52-46f7-8278-5e2210713be9"
+SparseMatricesCSR = "a0a7dd2c-ebf4-11e9-1f05-cf50bc540ca1"
 
 [extensions]
-HYPREPartitionedArrays = "PartitionedArrays"
+HYPREPartitionedArrays = ["PartitionedArrays", "SparseMatricesCSR"]
+HYPRESparseMatricesCSR = "SparseMatricesCSR"
 
 [compat]
 CEnum = "0.4, 0.5"
@@ -27,7 +29,8 @@ julia = "1.6"
 [extras]
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 PartitionedArrays = "5a9dfac6-5c52-46f7-8278-5e2210713be9"
+SparseMatricesCSR = "a0a7dd2c-ebf4-11e9-1f05-cf50bc540ca1"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
-test = ["LinearAlgebra", "PartitionedArrays", "Test"]
+test = ["LinearAlgebra", "PartitionedArrays", "SparseMatricesCSR", "Test"]
diff --git a/ext/HYPREPartitionedArrays.jl b/ext/HYPREPartitionedArrays.jl
index 4fed004..f66dfbe 100644
--- a/ext/HYPREPartitionedArrays.jl
+++ b/ext/HYPREPartitionedArrays.jl
@@ -184,7 +184,7 @@ function Internals.get_proc_rows(A::Union{PSparseMatrix, PVector})
     return ilower, iupper
 end
 
-function HYPREMatrix(B::PSparseMatrix)
+function HYPRE.HYPREMatrix(B::PSparseMatrix)
     # Use the same communicator as the matrix
     comm = Internals.get_comm(B)
     # Fetch rows owned by this process
@@ -206,7 +206,7 @@ end
 # PartitionedArrays.PVector -> HYPREVector #
 ############################################
 
-function HYPREVector(v::PVector)
+function HYPRE.HYPREVector(v::PVector)
     # Use the same communicator as the matrix
     comm = Internals.get_comm(v)
     # Fetch rows owned by this process
diff --git a/ext/HYPRESparseMatricesCSR.jl b/ext/HYPRESparseMatricesCSR.jl
new file mode 100644
index 0000000..f046a0e
--- /dev/null
+++ b/ext/HYPRESparseMatricesCSR.jl
@@ -0,0 +1,80 @@
+module HYPRESparseMatricesCSR
+
+using HYPRE.LibHYPRE: @check, HYPRE_BigInt, HYPRE_Complex, HYPRE_Int
+using HYPRE: HYPRE, HYPREMatrix, HYPRESolver, HYPREVector, HYPRE_IJMatrixSetValues, Internals
+using MPI: MPI
+using SparseArrays: SparseArrays, nonzeros, nzrange
+using SparseMatricesCSR: SparseMatrixCSR, colvals
+
+
+##################################
+# SparseMatrixCSR -> HYPREMatrix #
+##################################
+
+function Internals.to_hypre_data(A::SparseMatrixCSR, ilower, iupper)
+    Internals.check_n_rows(A, ilower, iupper)
+    nnz = SparseArrays.nnz(A)
+    A_cols = colvals(A)
+    A_vals = nonzeros(A)
+
+    # Initialize the data buffers HYPRE wants
+    nrows = HYPRE_Int(iupper - ilower + 1)      # Total number of rows
+    ncols = Vector{HYPRE_Int}(undef, nrows)     # Number of colums for each row
+    rows = collect(HYPRE_BigInt, ilower:iupper) # The row indices
+    cols = Vector{HYPRE_BigInt}(undef, nnz)     # The column indices
+    values = Vector{HYPRE_Complex}(undef, nnz)  # The values
+
+    # Loop over the rows and collect all values
+    k = 0
+    @inbounds for i in 1:size(A, 1)
+        nzr = nzrange(A, i)
+        ncols[i] = length(nzr)
+        for j in nzr
+            k += 1
+            col = A_cols[j]
+            val = A_vals[j]
+            cols[k] = col
+            values[k] = val
+        end
+    end
+    @assert nnz == k
+    @assert nrows == length(ncols) == length(rows)
+    return nrows, ncols, rows, cols, values
+end
+
+
+# Note: keep in sync with the SparseMatrixCSC method
+function HYPRE.HYPREMatrix(comm::MPI.Comm, B::SparseMatrixCSR, ilower, iupper)
+    A = HYPREMatrix(comm, ilower, iupper)
+    nrows, ncols, rows, cols, values = Internals.to_hypre_data(B, ilower, iupper)
+    @check HYPRE_IJMatrixSetValues(A, nrows, ncols, rows, cols, values)
+    Internals.assemble_matrix(A)
+    return A
+end
+
+# Note: keep in sync with the SparseMatrixCSC method
+function HYPRE.HYPREMatrix(B::SparseMatrixCSR, ilower=1, iupper=size(B, 1))
+    return HYPREMatrix(MPI.COMM_SELF, B, ilower, iupper)
+end
+
+
+####################################
+# SparseMatrixCSR solver interface #
+####################################
+
+# Note: keep in sync with the SparseMatrixCSC method
+function HYPRE.solve(solver::HYPRESolver, A::SparseMatrixCSR, b::Vector)
+    hypre_x = HYPRE.solve(solver, HYPREMatrix(A), HYPREVector(b))
+    x = copy!(similar(b, HYPRE_Complex), hypre_x)
+    return x
+end
+
+# Note: keep in sync with the SparseMatrixCSC method
+function HYPRE.solve!(solver::HYPRESolver, x::Vector, A::SparseMatrixCSR, b::Vector)
+    hypre_x = HYPREVector(x)
+    HYPRE.solve!(solver, hypre_x, HYPREMatrix(A), HYPREVector(b))
+    copy!(x, hypre_x)
+    return x
+end
+
+end # module HYPRESparseMatricesCSR
diff --git a/src/HYPRE.jl b/src/HYPRE.jl
index 2c2a3e8..7e8e105 100644
--- a/src/HYPRE.jl
+++ b/src/HYPRE.jl
@@ -4,7 +4,6 @@ module HYPRE
 
 using MPI: MPI
 using SparseArrays: SparseArrays, SparseMatrixCSC, nonzeros, nzrange, rowvals
-using SparseMatricesCSR: SparseMatrixCSR, colvals
 
 export HYPREMatrix, HYPREVector
 
@@ -184,9 +183,9 @@ function Base.zero(b::HYPREVector)
     return x
 end
 
-######################################
-# SparseMatrixCS(C|R) -> HYPREMatrix #
-######################################
+##################################
+# SparseMatrixCSC -> HYPREMatrix #
+##################################
 
 function Internals.check_n_rows(A, ilower, iupper)
     if size(A, 1) != (iupper - ilower + 1)
@@ -233,38 +232,8 @@ function Internals.to_hypre_data(A::SparseMatrixCSC, ilower, iupper)
     return nrows, ncols, rows, cols, values
 end
 
-function Internals.to_hypre_data(A::SparseMatrixCSR, ilower, iupper)
-    Internals.check_n_rows(A, ilower, iupper)
-    nnz = SparseArrays.nnz(A)
-    A_cols = colvals(A)
-    A_vals = nonzeros(A)
-
-    # Initialize the data buffers HYPRE wants
-    nrows = HYPRE_Int(iupper - ilower + 1)      # Total number of rows
-    ncols = Vector{HYPRE_Int}(undef, nrows)     # Number of colums for each row
-    rows = collect(HYPRE_BigInt, ilower:iupper) # The row indices
-    cols = Vector{HYPRE_BigInt}(undef, nnz)     # The column indices
-    values = Vector{HYPRE_Complex}(undef, nnz)  # The values
-
-    # Loop over the rows and collect all values
-    k = 0
-    @inbounds for i in 1:size(A, 1)
-        nzr = nzrange(A, i)
-        ncols[i] = length(nzr)
-        for j in nzr
-            k += 1
-            col = A_cols[j]
-            val = A_vals[j]
-            cols[k] = col
-            values[k] = val
-        end
-    end
-    @assert nnz == k
-    @assert nrows == length(ncols) == length(rows)
-    return nrows, ncols, rows, cols, values
-end
-
-function HYPREMatrix(comm::MPI.Comm, B::Union{SparseMatrixCSC,SparseMatrixCSR}, ilower, iupper)
+# Note: keep in sync with the SparseMatrixCSR method
+function HYPREMatrix(comm::MPI.Comm, B::SparseMatrixCSC, ilower, iupper)
     A = HYPREMatrix(comm, ilower, iupper)
     nrows, ncols, rows, cols, values = Internals.to_hypre_data(B, ilower, iupper)
     @check HYPRE_IJMatrixSetValues(A, nrows, ncols, rows, cols, values)
@@ -272,8 +241,10 @@ function HYPREMatrix(comm::MPI.Comm, B::Union{SparseMatrixCSC,SparseMatrixCSR},
     return A
 end
 
-HYPREMatrix(B::Union{SparseMatrixCSC,SparseMatrixCSR}, ilower=1, iupper=size(B, 1)) =
-    HYPREMatrix(MPI.COMM_SELF, B, ilower, iupper)
+# Note: keep in sync with the SparseMatrixCSC method
+function HYPREMatrix(B::SparseMatrixCSC, ilower=1, iupper=size(B, 1))
+    return HYPREMatrix(MPI.COMM_SELF, B, ilower, iupper)
+end
 
 #########################
 # Vector -> HYPREVector #
@@ -504,6 +475,7 @@ include("solver_options.jl")
 # Compatibility for Julias that doesn't support package extensions
 if !(isdefined(Base, :get_extension))
     include("../ext/HYPREPartitionedArrays.jl")
+    include("../ext/HYPRESparseMatricesCSR.jl")
 end
 
 end # module HYPRE
diff --git a/src/solvers.jl b/src/solvers.jl
index 1c8df03..c242707 100644
--- a/src/solvers.jl
+++ b/src/solvers.jl
@@ -51,18 +51,19 @@ See also [`solve`](@ref).
 solve!(pcg::HYPRESolver, x::HYPREVector, A::HYPREMatrix, ::HYPREVector)
 
 
-########################################
-# SparseMatrixCS(C|R) solver interface #
-########################################
+####################################
+# SparseMatrixCSC solver interface #
+####################################
 
-# TODO: This could use the HYPRE compile flag for sequential mode to avoid MPI overhead
-
-function solve(solver::HYPRESolver, A::Union{SparseMatrixCSC,SparseMatrixCSR}, b::Vector)
+# Note: keep in sync with the SparseMatrixCSR method
+function solve(solver::HYPRESolver, A::SparseMatrixCSC, b::Vector)
     hypre_x = solve(solver, HYPREMatrix(A), HYPREVector(b))
     x = copy!(similar(b, HYPRE_Complex), hypre_x)
     return x
 end
-function solve!(solver::HYPRESolver, x::Vector, A::Union{SparseMatrixCSC,SparseMatrixCSR}, b::Vector)
+
+# Note: keep in sync with the SparseMatrixCSR method
+function solve!(solver::HYPRESolver, x::Vector, A::SparseMatrixCSC, b::Vector)
     hypre_x = HYPREVector(x)
     solve!(solver, hypre_x, HYPREMatrix(A), HYPREVector(b))
     copy!(x, hypre_x)
diff --git a/test/runtests.jl b/test/runtests.jl
index df67647..ab406c1 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -731,18 +731,24 @@ end
 
 @testset "solve with SparseMatrixCS(C|R)" begin
     # Setup
-    A = sprand(100, 100, 0.05); A = A'A + 5I
+    CSC = sprand(100, 100, 0.05); CSC = CSC'CSC + 5I
+    CSR = sparsecsr(findnz(CSC)..., size(CSC)...)
     b = rand(100)
-    x = zeros(100)
+    xcsc = zeros(100)
+    xcsr = zeros(100)
     # Solve
     tol = 1e-9
     pcg = HYPRE.PCG(; Tol = tol)
     ## solve!
-    HYPRE.solve!(pcg, x, A, b)
-    @test x ≈ A \ b atol=tol
+    HYPRE.solve!(pcg, xcsc, CSC, b)
+    @test xcsc ≈ CSC \ b atol=tol
+    HYPRE.solve!(pcg, xcsr, CSR, b)
+    @test xcsr ≈ CSC \ b atol=tol # TODO: CSR \ b fails
     ## solve
-    x = HYPRE.solve(pcg, A, b)
-    @test x ≈ A \ b atol=tol
+    xcsc = HYPRE.solve(pcg, CSC, b)
+    @test xcsc ≈ CSC \ b atol=tol
+    xcsr = HYPRE.solve(pcg, CSR, b)
+    @test xcsr ≈ CSC \ b atol=tol # TODO: CSR \ b fails
 end
 
 @testset "MPI execution" begin